Jump lists, including jump list tasks and categorized jump list destinations, are a Windows 7 feature that's been accessible to Windows applications for quite a long time.
It's indeed awesome that Internet Explorer 9 pinned sites exposes the jump list API through JavaScript to pages on the web. A jump list is the whole menu that shows up when your right-click an icon on the taskbar; jump list tasks are the section of the jump list called "Tasks"; and the rest of the jump list contains jump list items, or destinations. Too bad the terms are misleadingly unaligned with the Windows 7 vocabulary.

http://blogs.microsoft.co.il/blogs/gilf/archive/2010/10/11/using-overlay-icon-api-to-make-client-notifications-in-ie9.aspx
<h3>Dynamic Tasks are defined using JavaScript <abbr>api</abbr>s</h3>
<p><abbr>ie9</abbr> enables developers to access the <code class="vjs">SiteMode Overlay Icon Behavior</code>, a feature of <strong>site pinning</strong>. <strong>Overlay Icon <abbr>api</abbr></strong> includes two <b>methods</b>: <code class="vjs">msSiteModeSetIconOverlay</code> and <code class="vjs">msSiteModeClearIconOverlay</code>.</p>
<dl>
  <dt><dfn><code class="vjs">msSiteModeSetIconOverlay</code></dfn></dt>
  <dd><p><b>method</b> enables communication alerts, notifications, and statuses to the user via applying an icon atop of the site's existing icon. Takes two <b>parameters</b>: <abbr title="Uniform Resource Identifier">uri</abbr> of an image and a <b>tooltip</b> value.</p></dd>
  <dt><dfn><code class="vjs">msSiteModeClearIconOverlay</code></dfn></dt>
  <dd><p><b>method</b> clears any existing overlay icon.</p></dd>
</dl>
http://www.sitepoint.com/using-pinned-sites-to-build-customer-relationships/
http://www.sitepoint.com/pinned-sites-with-internet-explorer-9-and-windows-7/
http://windowsteamblog.com/ie/b/ie/archive/2011/01/07/huffington-post-reinventing-the-big-news-experience-with-ie9-pinned-sites.aspx
http://msdn.microsoft.com/en-us/ie/dd797411.aspx
http://ie.microsoft.com/testdrive/Browser/IconEditor/Default.html" title="X-Icon Editor
http://ie.microsoft.com/testdrive/Default.html" title="Internet Explorer Test Drive &#45; Follow the Progress of the Internet Explorer Developer Platform">
http://www.xiconeditor.com/
http://buildmobile.com/get-pinned-windows-phone-7-live-tiles/
http://buildmypinnedsite.com/


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