It’s really out now. WP 2.5 boasts a completely redesigned administration interface, a new media uploader, built-in avatar support and much more. I’ve been using the release candidates on my personal blog for the past two weeks already and it’s solid. This site will be updated soon.
Go download it from WordPress.org, and admire their overhauled design while you’re there.
Congrats to the WordPress team and Happy Cog on a job well done!