It’s here and it’s “Thelonious”.
Now unless you are capable of
- Backing up your WordPress blog completely
- Performing the manual upgrade by hand
- Capable of restoring your file and database backup 100% yourself in case something goes seriously wrong
then consider waiting before adopting WordPress 3.0 on your blog.
The 3.0 release is BIG and things will fail on some setups. At this moment, there is no reason to rush into this release.
At some point soon, yes do upgrade. Keeping current is valuable and makes your blog easier to obtain support. But for now consider waiting.