Warning: this article includes dangerous levels of sarcasm, and should not be read by young children or pregnant women.
Vista supports an expensive (for you) increase in DRM          [A] [B] [C]. Buy it only if you support your digital rights being "managed". Video drivers that check the "integrity" of their connections over 30 times a second can't be that much slower, right? Having your video driver "revoked" out from under you is a small price to pay in order to add several layers of new things you've gotta check when things go wrong.
Maybe you just like to drop $250-$400 on improvements that even supporters characterize as "incremental"     , or have trouble understanding. That sidebar will certainly not represent a distraction that will get old inside a few months, or be disabled by your network admin sooner.