My favorite highlights so far:
- Integrated spell checking: Don’t need an extension for this anymore, and it’s always good to trim down the extension list
- Integrated RSS feed recognition and subscription, integrated with Google Reader: Previous versions had rudimentary feed support, but nothing like it is now, which is pretty much exactly how I’d like it. It will allow you to use Google Reader as your feed manager rather than their built-in one (which I didn’t really like), and once you’ve set that preference, you can just click on any feed link and it will ask you if you want to subscribe to it in Google Reader.
- The cake that the IE dev team sent to the Mozilla dev team, congratulating them for their release.