For anyone installing updates post SP1 be careful because it lets you install older updates when newer ones are supposed to be integrated.
That is Microsoft for you...
For Example, an old update like KB927546 will install on Vista with just SP1.
However, a newer revision of the update appears to already be integrated.
http://technet2.microsoft.com/windowsvista...3.mspx?mfr=true
Wouldn't this cause system instability for some updates?