I’ve installed it over at BeClan and will shortly be doing likewise here. It’s a significant upgrade – well done to all on the WP team!
The best feature I’ve found I have mixed feelings about. Akismet is a very neat distributed anti-spam filter, but it requires creating an account at wordpress.com to get a code! That is so lame it’s not even funny and really spoils what is otherwise an excellent idea that, from what I’ve seen so far, works exceedingly well and should make the business of hosting a blog a lot more painless. I can understand why the want people to ask for a code, but needing to register for a blog first? Come on guys, join the real world and stop being so stupid.