Funny, though, how versions of this UAC hole keep popping up anyway.
In addition, there are other problems like Windows 7'x XP mode, which bypasses all the improvements made in Vista and Windows 7. Again, it all comes down to all of Windows security improvements amounting to being just layer over another of security over its fatal single-user, non-networked genetics.
That's why Linux and Mac OS X, which is based on BSD Unix at its heart, are fundamentally safer. Their design forefathers were multi-user, networked systems. From their very beginning, they were built to deal with a potentially hostile world. Windows wasn't. It's really that simple.
On top of all that is the reason that Windows apologists always give: Windows is more popular so it gets attacked more often. That's true. But, so what? You're still going to get hacked.
For you, as a user, running Windows means that your PC will be attacked on an almost daily basis. Hacked Web sites, spam carrying malware, it's almost all meant for little old you and your Windows PC. Even with constant patching and added security programs, you're always going to be in danger of having your PC hijacked.
In short, to return to the beginning, Windows security is now, always has been, and always will be, bad. If you want a secure computer, you'll be better off trying with either a Linux desktop or a Mac. Like it or lump it, that's just the way it is.