“We’ve got a new bugfix and security release for both of our actively maintained branches of WordPress. Version 2.1.1 includes about 30 bug fixes, mostly minor things around encoding, XML-RPC, the object cache, and HTML code. It’s available for immediate download on our download page.
Version 2.0.9 only includes the security update, which was around the code we use to prevent XSS. You can download it from our release archive. […]
This is a low-to-medium priority update recommended for all WordPress users.”