"if you like a built in backdoor to the NSA, go ahead and gloat"
Mwahahaha...I know more than they regarding this particular license of Win 7...if "they" can't fix "that", I doubt I'm in any trouble. NSA or not.
"Why not run something that isn't broken?"
Well, I wasn't so much for Vista. And Leopard (OSX 10.5) had limited support for 64-bit systems and multicore setups. And, the system starts up / shuts down much quicker than previously.
Why is Apple offering Snow Leopard for next to nothing? They know that 10.6 is an "under-the hood" update...they compensated for technology which wasn't offered at the time, which is now. They made Snow Leopard what "regular" Leopard ought to have been. At least, with 20/20 hindsight. However, the major update with a minor price tag is uncharacteristic. Interpret that how you will; I've already offered my opinion.
The same is not the case, of course, for Win 7. Vista demanded too much, and was far too sluggish -- a Frankenstein monster.
Nevertheless, manytimes hardware makes obsolete the current software. See, for example, 64-bit processing, multiple cores, and (at least in the case of XP) ability to address more than 4GB of RAM.
That's the reason to "run something that isn't broken".