Istartedsomething has some news on Vista hotfixes improves file performance, reliability, standby/resume, games graphics and global warming.
If you were one of the many betting on performance and reliability improvements in anticipation for Windows Vista Service Pack 1, then your winnings has arrived early, in fact some can already claim the jackpot. Winning lotto balls KB938194 and KB938979 for Windows Vista were distributed today to a group of Windows Server 2008 testers which is said to fix many of the mass-reported performance issues in Vista and even some unexpected improvements.
Sadly these aren't available to the common folk yet, but they are expected to be coming out via Windows Update "in the coming weeks", unless you're feeling very brave and want to download the patches from some random site on the net (I'd recommend not doing this by the way :)
Another post on Vista SP1 is here.