Live Titles: When a website offers a microsummary (a regularly updated summary of the most important information on a Web page), users can create a bookmark with a "Live Title". Compact enough to fit in the space available to a bookmark label, they provide more useful information about pages than static page titles, and are regularly updated with the latest information. There are several websites that can be bookmarked with Live Titles, and even more add-ons to generate Live Titles for other popular websites.One significant innovation in FF2 is microsummary proposed by Myk Melez. Unlike email or RSS aggregator, it can track a specific thing and be displayed as a headline. The default update interval in 30 min, but just add "browser.microsummary.updateInterval" to be 1 in about:config and all live titles will refresh as soon as possible (still 1 min).
Now, only some sites have microsummary embedded, so microsummary generators are needed for other sites. A good way is to use this Microsummary Generator Builder to "generate a microsummary generator", install it, and bookmark the live title to Bookmarks Toolbar.
With live title, the specific info like CNN headline will really be the "head line" in FF2. It is suitable when the past info is not as important (otherwise, use an aggregator). The missing piece may be sound notification once any of the live titles is updated.