I can sum up my Firefox 2.0 experiences pretty neatly: I like it better than Firefox 1.5, but it's not a major release of the browser. In fact, it's stretching it to call this Firefox 2.0. Something like version 1.8 would be more realistic.
About 80 percent of the extensions I use are supported, and I'm sure the others will come relatively quickly. With the new features added in this version, of course, some extensions have become unnecessary: In my Firefox setup, Firefox 2.0 obviated the need for five extensions and another two customizations that I apply to all Firefox 1.x installations. To my way of thinking, that's a very good thing.
Finally, Firefox 2 seems a tad faster to me than the 1.x versions of Firefox. And that's it -- those are the true high points.
Other nice-to-haves in the new Mozilla browser include the ability to preview RSS feeds and a facility for subscribing to feeds that works with most feed readers. Firefox 2 offers on-the-fly inline spell checking for Web forms, blogs, and discussion posts. It offers built-in ID theft phishing protection. There's even a feature for resuming a previous browser session, called Session Restore, and you can reopen an accidentally closed tab. Although there are other new features and functions, these are the ones that matter to most people.
One new feature, Live Titles, is a little puzzling at first. (Do you think there's a reason why both Mozilla and Microsoft are using the "live" moniker?) Live Titles are content descriptions added to text labels in your bookmarks. Web sites must be specifically enabled for this feature for Firefox 2.0, so it's not widely useful yet. (Mozilla offers these sites as Live Titles examples - http://people.mozilla.com/~myk/microsummaries/sites/) The advantage of this feature is that Webmasters can change the Live Title information as content changes on their pages, and the text automatically will change in your bookmark, giving you a textual indication of what's new. It's a good basic idea that doesn't currently offer a lot of advantage yet.