The key new features of Firefox 2.0 beta (with brief commentary) are:

  1. Integrated spell-checker - no more excuse for poor spelling in form data
  2. Bookmarked web site summary - small updated headlines that sites can create that display in the bookmark sidebar in Firefox
  3. Crashed session recovery - finally I can replace tab browser extension
  4. Re-open recently closed tabs - this one is a life-saver
  5. Anti-phishing warning popup - I hate popups but will let this one slide.
  6. Search suggestion - live dropdown of suggested terms while searching
  7. Tab close button on tabs - Personally I like ctrl-w better, a close button on every tab just makes it more crowded, not convenient
  8. RSS feed preview - provides information on an RSS feed when the user is subscribing to it

You can download and test it here.