Hmm...Well, I'm running SP2 on my home computer and haven't had any problems with it, though I don't do any port scanning from that machine. And I installed in right after it came out for testing (I know, probably not the brightest idea in the world). So far, so good!

<edit> Correction, I have had one problem -- CD-RW drive stopped working and computer locks up when I run Ahead Nero...I'm thinking a corrupted driver maybe? I don't think it has anything to do with SP2, but given the timing I guess it's a possibility...hmm...I'll have to research that.