Good news Windows 7 beta users: your opinion matters!
As announced on the Engineering Windows 7 blog, UAC behavior has been changed in two key ways. First, confirmation is now required when any UAC changes are initiated. Second, the UAC control panel itself will now run in a "high integrity process" that can't be compromised using mechanisms like sendkeys.
Yes, it's fantastic news that Microsoft has fixed an important security issue. But Microsoft does have a good track record as far as security goes - just look how quickly they responded to the unconfirmed IE flaw.
There's something else important to take away from this: Microsoft is actually listening to what its beta users are saying, and they're willing to make changes based on feedback. It's encouraging to see this at work, and is certainly a good sign for users planning on making the move to Windows 7 once it's released.
Keep using your send feedback links, and keep commenting - Microsoft is listening this time around!