Roughly two and a half months after the 2.6.21 release, the next iteration of the powerhouse behind so many projects has come to market. Linux kernel 2.6.22 was just recently published, bringing with it a host of changes, bugfixes and new hardware support.
Most packaged-based distros can be expected to have a kernel update available soon, and some have already had the development candidates for this kernel available. A lot of driver issues were corrected in this release, for both old and new hardware alike.
One of the biggest things of note is a lot of enhanced wireless support, such as improved WPA implementation and a new interface for development. This may not mean much to a desktop user, but in the long run it will enable developers to create software to work with many devices much easier. You can read a user-friendly list of changes if you wish.