Andrew Nacin announced “After nearly 11 million downloads of WordPress 3.0 in just 42 days, we’re releasing WordPress 3.0.1.
This maintenance release addresses about 50 minor issues.”
There is also a warning posted “Note: If you downloaded 3.0.1 in the first 20 minutes of release (before 2200 UTC), you’ll want to reinstall it, which you can do right from your Updates screen. Our bad.”
Best to make a backup of your WordPress site before upgrading
List of files Revised at: http://codex.wordpress.org/Version_3.0.1
Download at: http://wordpress.org/