I’m sure most Firefox users are familiar with Live Bookmarks by now — bookmarks that point to RSS feeds, and update themselves as the feed is updated. Firefox 2 has now introduced Live Titles — page titles that also update themselves. If you’re using Firefox 2 and you want to see an example, go to woot.com and bookmark it. Rather than the typical name text field, you’ll see a combo box that lets you enter a static title, or choose one of woot’s two Live Titles, which is a brief description of the item currently being sold. Makes perfect sense for both woot and woot fans.
Live Titles are actually "microsummaries" which are easily implemented using a link tag with a rel value of "microsummary". For more information, check out this page on the Mozilla wiki. You can also find a list of microsummary-enabled sites here. And finally, check out the Firefox 2 Release Notes for more information on what’s new in Firefox 2.