Their download page is still reflecting Catalyst 12.1 from January, but there's already many Phoronix readers discussing the 12.2 release.
AMD still also doesn't publish the Linux release notes on the driver, but the changes that come to mind due to my encounters with the non-public development Catalyst drivers is that the 12.2 release stream isn't too exciting. There's various packaging script updates for different Linux distributions (as found on Phorogit), Radeon HD 7000 series support improvements, and a few bug-fixes. One bug-fix that is of interest to several Phoronix readers is one concerning X-Video playback.
What's not found in the Catalyst 12.2 driver is X.Org Server 1.12 support. There's also still not proper Radeon HD 7000 series "Southern Islands" support across the released hardware. Even for the Radeon HD 7950 that I'm testing under Linux and has been available for a while already, currently with the fglrx 8.95 release stream, it's still advertised as "unsupported hardware" via the pesky AMD watermark.
Those interested in downloading the Catalyst 12.2 Linux x86/x86_64 driver can find the download link from this Phoronix reader post.