I updated my system using the combo update. There are two ways to fix sound (for this particular motherboard - a Gigabyte H55M-S2V F3):
1) If using VoodooHDA, the 10.7.1 update will cause a kernel panic after reboot. Don't panic. Boot with Hackboot, reinstall Voodoo kexts using Multibeast 3.8.0 and everything will be ok after the next reboot.
2) If using GigabyteALC888bautoHP.kext, then reinstall AppleHDA.kext from 10.6.4 and HDAEnabler.kext into Lion/Library/Extensions using Kext Utility or Kext Helper B7, run System Utilities from Multibeast to rebuild cache and permissions, and you're good to go.
Everything else works, and I noticed a faster boot up sequence after the update. I had my Xeon X3440 running at 3.55 GHz before, but decided that I did not need that much horsepower. I toggled it down to 3.4 GHz instead, and the idle temps are running at a cool and steady 35-37 degrees Celsius for all 4 cores (maxing out at around 54-58 degrees Celsius at full load).