Apparently, there are a number of people reporting serious problems with this service pack that have rendered some machines totally useless, in need of a total reinstall to get them to work again. You might want to hold out installing this for a little while longer. Here is just a sampling of some of the articles related to this release.

http://www.pcworld.com/article/id,14581 … ticle.html

http://news.idg.no/cw/art.cfm?id=1659E1 … 23FDD85185

http://www.eweek.com/c/a/Desktops-and-N … -Continue/