After upgrading to Vista premium home on my Dell laptop my IE 7 stopped working. I still can connect to the internet through Mozilla and upgrades for the various programs connect to the internet and go forward without a hitch, but I can't get IE to work.
As a separate issue I noticed that the strength of my wireless connection went from excellent to good. During installation it eliminated the driver that came with my Intel pro and presumably replaced it with a compatible one but the signal is definitely weaker.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic