I confess, I'm mostly too lazy to test if graphics work after a new kernel update. Even if one reboots, finds graphics work, maybe (albeit highly unlikely) there will be some obscure side effect that one encounters later. Hence I simply rebuild the graphic driver as a matter of course.
Once one is familiar with a simple rebuild of the graphic driver (for a new kernel) its very fast to simply reboot to run level 3, and rebuild the graphic driver (for both ATI and nVidia graphics) and voila ... all should be wonderful.
I note audio "just worked" after the 2.6.27.37 update on 11.1, which is not a surprise. Still, I also note there are new alsa rpms packaged for the 2.6.27.37 kernel in case one had audio problems.
I had to rebuild Virtual Box after the 2.6.27.37 update. No problem as Virtual Box tells one EXACTLY what to do. But that simple fix has stumped MANY a new user and we could have some users new to Virtual Box report a problem.
I note my webcam driver just worked after the kernel update, although I did see a difference in how an ffmpeg based application worked with the web cam what should have been a full screen but was not (using an ATI driver) after the 2.6.27.37 update (and also after a proprietary ATI driver update). So something puzzling (but not worth the time fixing) was introduced there.
I have not yet updated my wife's PC to the 2.6.27.37 kernel (it uses an Atheros wireless) so I have not yet checked to see if it has a problem, but I seriously doubt it will, as her PC now uses the ath5k driver, as opposed to using the madwifi.