WGA, of course! Windows Genuine Advantage phones home.. Just another way for Microsoft to waste your bandwidth. If you do not install Windows Genuine Advantage, it will eventually sneak-up on you through Windows Updates. The only way to get around it is to patch it, and I believe those patches are still allowing XP to phone home.
Vista isn't worth the bother, yet. Too many hardware requirements, too few drivers, too many headaches; like all the Microsoft Beta-ware Version x.0 pre SP1 versions of their OS have been since Windows 3.0.
As long as third-parties such as Zone Alarm support XP, I'll stick with XP or I'll go Linux or Mac. At that point Microsoft had better have a better answer than Vista, or I won't be the only one they lose!
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