I have installed sp1 on my main retouching machine and have encountered no problems so far.
Improvements in network responsivness and file copying are certainly welcome.
The service pack is not in general distribution yet but may be available in the next few days. If I notice any problems I will report them here. Having said that your system will be in a different configuration than mine so dont assume that sp1 would do the same for you. Best to let the update mature for a few weeks so Microsoft can tune it.
As ever I need to be on the bleeding edge!
Stephen