diff --git a/resources/sql/patches/032.viewtime.sql b/resources/sql/patches/032.viewtime.sql
new file mode 100644
index 0000000000..455e3d7809
--- /dev/null
+++ b/resources/sql/patches/032.viewtime.sql
@@ -0,0 +1,6 @@
+CREATE TABLE phabricator_differential.differential_viewtime (
+  viewerPHID varchar(64) not null,
+  objectPHID varchar(64) not null,
+  viewTime int unsigned not null,
+  PRIMARY KEY (viewerPHID, objectPHID)
+);
diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
index 6527f5a0fd..1aded6c0a3 100644
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -158,6 +158,7 @@ phutil_register_library_map(array(
     'DifferentialSubscribeController' => 'applications/differential/controller/subscribe',
     'DifferentialTasksAttacher' => 'applications/differential/tasks',
     'DifferentialUnitStatus' => 'applications/differential/constants/unitstatus',
+    'DifferentialViewTime' => 'applications/differential/storage/viewtime',
     'DiffusionBranchInformation' => 'applications/diffusion/data/branch',
     'DiffusionBranchQuery' => 'applications/diffusion/query/branch/base',
     'DiffusionBranchTableView' => 'applications/diffusion/view/branchtable',
@@ -585,6 +586,7 @@ phutil_register_library_map(array(
     'DifferentialRevisionUpdateHistoryView' => 'AphrontView',
     'DifferentialRevisionViewController' => 'DifferentialController',
     'DifferentialSubscribeController' => 'DifferentialController',
+    'DifferentialViewTime' => 'DifferentialDAO',
     'DiffusionBranchTableView' => 'DiffusionView',
     'DiffusionBrowseController' => 'DiffusionController',
     'DiffusionBrowseFileController' => 'DiffusionController',
diff --git a/src/applications/differential/controller/revisionlist/DifferentialRevisionListController.php b/src/applications/differential/controller/revisionlist/DifferentialRevisionListController.php
index af365b56ad..177a7e0c4f 100644
--- a/src/applications/differential/controller/revisionlist/DifferentialRevisionListController.php
+++ b/src/applications/differential/controller/revisionlist/DifferentialRevisionListController.php
@@ -90,6 +90,16 @@ class DifferentialRevisionListController extends DifferentialController {
           ),
         ),
       ),
+      'updates' => array(
+        'name' => 'Updates',
+        'queries' => array(
+          array(
+            'query' => DifferentialRevisionListData::QUERY_UPDATED_SINCE,
+            'header' =>
+              'Diffs that have been updated since you\'ve last viewed them',
+          ),
+        ),
+      ),
       '<hr />',
       'All Revisions',
       'allopen' => array(
diff --git a/src/applications/differential/controller/revisionview/DifferentialRevisionViewController.php b/src/applications/differential/controller/revisionview/DifferentialRevisionViewController.php
index 5a03483b2e..835250f9f8 100644
--- a/src/applications/differential/controller/revisionview/DifferentialRevisionViewController.php
+++ b/src/applications/differential/controller/revisionview/DifferentialRevisionViewController.php
@@ -205,6 +205,8 @@ class DifferentialRevisionViewController extends DifferentialController {
     $comment_form->setUser($user);
     $comment_form->setDraft($draft);
 
+    $this->updateViewTime($user->getPHID(), $revision->getPHID());
+
     return $this->buildStandardPageResponse(
       '<div class="differential-primary-pane">'.
         $revision_detail->render().
@@ -593,6 +595,14 @@ class DifferentialRevisionViewController extends DifferentialController {
     return array($changesets, $vs_map);
   }
 
+  private function updateViewTime($user_phid, $revision_phid) {
+    $view_time =
+      id(new DifferentialViewTime())
+        ->setViewerPHID($user_phid)
+        ->setObjectPHID($revision_phid)
+        ->setViewTime(time())
+        ->replace();
+  }
 }
 /*
 
diff --git a/src/applications/differential/controller/revisionview/__init__.php b/src/applications/differential/controller/revisionview/__init__.php
index 41a5ec6d22..3308871f23 100644
--- a/src/applications/differential/controller/revisionview/__init__.php
+++ b/src/applications/differential/controller/revisionview/__init__.php
@@ -15,6 +15,7 @@ phutil_require_module('phabricator', 'applications/differential/storage/comment'
 phutil_require_module('phabricator', 'applications/differential/storage/diffproperty');
 phutil_require_module('phabricator', 'applications/differential/storage/inlinecomment');
 phutil_require_module('phabricator', 'applications/differential/storage/revision');
+phutil_require_module('phabricator', 'applications/differential/storage/viewtime');
 phutil_require_module('phabricator', 'applications/differential/view/addcomment');
 phutil_require_module('phabricator', 'applications/differential/view/changesetlistview');
 phutil_require_module('phabricator', 'applications/differential/view/difftableofcontents');
diff --git a/src/applications/differential/data/revisionlist/DifferentialRevisionListData.php b/src/applications/differential/data/revisionlist/DifferentialRevisionListData.php
index c6c8f80540..afa81d7c2f 100644
--- a/src/applications/differential/data/revisionlist/DifferentialRevisionListData.php
+++ b/src/applications/differential/data/revisionlist/DifferentialRevisionListData.php
@@ -29,6 +29,7 @@ class DifferentialRevisionListData {
   const QUERY_PHIDS                    = 'phids';
   const QUERY_CC                       = 'cc';
   const QUERY_ALL_OPEN                 = 'all-open';
+  const QUERY_UPDATED_SINCE            = 'updated-since';
 
   private $ids;
   private $filter;
@@ -170,6 +171,9 @@ class DifferentialRevisionListData {
           'revision.phid in (%Ls)',
           $this->ids);
         break;
+      case self::QUERY_UPDATED_SINCE:
+        $this->revisions = $this->loadAllUpdated();
+        break;
     }
 
     return $this->revisions;
@@ -183,6 +187,31 @@ class DifferentialRevisionListData {
     );
   }
 
+  private function loadAllUpdated() {
+    $revision = new DifferentialRevision();
+    $min_view_time = (int)PhabricatorEnv::getEnvConfig('updates.min-view-time');
+
+    $data = queryfx_all(
+      $revision->establishConnection('r'),
+      'SELECT DISTINCT revision.* FROM %T revision
+        JOIN %T rel ON rel.revisionID = revision.id
+          AND (rel.objectPHID in (%Ls) OR revision.authorPHID in (%Ls))
+        LEFT JOIN %T viewtime ON viewtime.viewerPHID in (%Ls)
+          AND viewtime.objectPHID = revision.phid
+        WHERE GREATEST(%d, IFNULL(viewtime.viewTime, 0)) < revision.dateModified
+        %Q',
+      $revision->getTableName(),
+      DifferentialRevision::RELATIONSHIP_TABLE,
+      $this->ids,
+      $this->ids,
+      DifferentialRevision::TABLE_VIEW_TIME,
+      $this->ids,
+      $min_view_time,
+      $this->getOrderClause());
+    return $revision->loadAllFromArray($data);
+  }
+
+
   private function loadAllOpen() {
     return $this->loadAllWhere('status in (%Ld)', $this->getOpenStatuses());
   }
diff --git a/src/applications/differential/data/revisionlist/__init__.php b/src/applications/differential/data/revisionlist/__init__.php
index 166a7864cf..846363efa2 100644
--- a/src/applications/differential/data/revisionlist/__init__.php
+++ b/src/applications/differential/data/revisionlist/__init__.php
@@ -8,6 +8,7 @@
 
 phutil_require_module('phabricator', 'applications/differential/constants/revisionstatus');
 phutil_require_module('phabricator', 'applications/differential/storage/revision');
+phutil_require_module('phabricator', 'infrastructure/env');
 phutil_require_module('phabricator', 'storage/queryfx');
 
 phutil_require_module('phutil', 'utils');
diff --git a/src/applications/differential/storage/revision/DifferentialRevision.php b/src/applications/differential/storage/revision/DifferentialRevision.php
index ed72902df1..910e4bd290 100644
--- a/src/applications/differential/storage/revision/DifferentialRevision.php
+++ b/src/applications/differential/storage/revision/DifferentialRevision.php
@@ -39,6 +39,7 @@ class DifferentialRevision extends DifferentialDAO {
   private $commits;
 
   const RELATIONSHIP_TABLE    = 'differential_relationship';
+  const TABLE_VIEW_TIME       = 'differential_viewtime';
   const TABLE_COMMIT          = 'differential_commit';
 
   const RELATION_REVIEWER     = 'revw';
diff --git a/src/applications/differential/storage/viewtime/DifferentialViewTime.php b/src/applications/differential/storage/viewtime/DifferentialViewTime.php
new file mode 100644
index 0000000000..2df8075781
--- /dev/null
+++ b/src/applications/differential/storage/viewtime/DifferentialViewTime.php
@@ -0,0 +1,43 @@
+<?php
+
+/*
+ * Copyright 2011 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+class DifferentialViewTime extends DifferentialDAO {
+
+  protected
+    $viewerPHID,
+    $objectPHID,
+    $viewTime;
+
+  protected function getConfiguration() {
+    return array(
+      self::CONFIG_OPTIMISTIC_LOCKS => false,
+      self::CONFIG_IDS              => self::IDS_MANUAL,
+      self::CONFIG_TIMESTAMPS       => false,
+    );
+  }
+
+  // Primary key is (viewerPHID, objectPHID)
+  public function getIDKey() {
+    return null;
+  }
+
+  protected function shouldInsertWhenSaved() {
+    return true;
+  }
+}
+
diff --git a/src/applications/differential/storage/viewtime/__init__.php b/src/applications/differential/storage/viewtime/__init__.php
new file mode 100644
index 0000000000..905e57f5c9
--- /dev/null
+++ b/src/applications/differential/storage/viewtime/__init__.php
@@ -0,0 +1,13 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('phabricator', 'applications/differential/storage/base');
+
+
+phutil_require_source('DifferentialViewTime.php');
+