List of the major changes done to each Linux kernel release. Other places to get news about the Linux kernel are [http://lwn.net/Kernel/ LWN kernel status], [http://lwn.net/Articles/2.6-kernel-api/ LWN list of API changes in 2.6], or [http://www.lkml.org www.lkml.org]. List of changes of older releases can be found at Linux26Changes. If you're going to add something here look first at LinuxChangesRules!
Discuss the latest Linux kernel changes on the [http://forum.kernelnewbies.org/list.php?4 Kernelnewbies web forum].
Lists of changes in various releases
[http://kernelnewbies.org/known_regressions_2621 regressions in 2.6.21]
[http://kernelnewbies.org/known_regressions_2622 regressions in 2.6.22]
[http://kernelnewbies.org/known_regressions regressions in 2.6.23]
[http://kernelnewbies.org/known_regressions_stats regression stats (various versions)]