And yet, if you're an administrator it's trivial to escalate to SYSTEM. That's the whole danger of granting unnecessarily broad admin privileges.

You need local admin privileges to install Framework 3.5 SP1. And remember - if an application masquerades with local admin privileges, it can do WHATEVER it wants.

More like appending the version of the .NET CLR to the UA string, so that ClickOnce or XBAP applications can install through Firefox instead of requiring IE. I can testify (looking at my UA right now) that it does not change anything else and leaves the Firefox name intact. Of course, to find this out you might have to research or think about your answer instead of assuming evil behavior on Microsoft's part...

GTA4 kills proc and not GPU so much - I have a GTX260 Core 216 and a Quad-core Q9550, and I get an easy 40 FPS with medium textures enabled. I hear it's supposed to go higher when Nvidia releases their new drivers. In any case, Steam Forums was having a shootout in many threads when GTA4 was released and there's a pretty clear correlation between processor power and higher framerates. It's also supposed to be 64-bit optimized so I might be getting a boost from running 64-bit Vista.