I downloaded Firefox 3 yesterday, and was pleasantly surprised that most of the extensions and themes which I use were compatible. The only ones not yet updated were Tab Effect, which looks cool but isn't really essential, and Am I On Myspace.com?, which provides a great warning if you inadvertently stray onto any Myspace pages. How will I cope without this protection?!

For the geekily inclined, the Add-ons I use are:

1. AdBlock Plus
2. Colorful Tabs
3. Download Helper
4. Facebook Toolbar
5. FootieFox
6. ForcastFox
7. Google Toolbar
8. IE Tab
9. PDF Download
10. Shareaholic
11. StumbleUpon
12. TwitterFox
13. Undo Closed Tab
14. US English Dictionary
15. WOT (Web of Trust)