It has been almost two weeks since the release of the Linux 2.6.31-rc5 kernel but this afternoon there is a new kernel available. Linus has made the release of Linux 2.6.31-rc6, which brings a number of small fixes throughout the Linux kernel...
My wifi using ath9k driver has been dropping the connection pretty frequently on -rc5 and -rc6. I don't remember if it was happening in -rc4. And the version in wireless-testing is worse, it freezes for several seconds at a time.