I Installed This as a microsoft update. And all it did was slow down vistas at boot up and caused intenet explorer 7 to freqently shut down with the err message Internet explorer. has casued a err and will shut down. I just reinstalled vista. Howie
The scope of an update is improvement. Even on running systems. The trite is backup before major changes. In this case SP1 is only for evaluation purpose and it has been given by MS only to testers and not to the public. I believe that when it will come officially there will not be bugs. Until then I think that it would be better to wait before of a permanent installation.