This is something I already have some experience with... MS tech people aren't any different than other tech support people. They have a pretty good understanding of how their product works, and a very good understanding of what they're suppose to say.** Also, the official story is usually more consistent and faster. "You'll have to buy a new copy" is a lot quicker than "well, sometimes you can, but you have to call, but don't be surprised if it doesn't work, blah blah".
Here's another thread on another forum where I was given untrue information from a MS CSR...
First thing's first, are you using an OEM install
zridling? If that's the case, the
official story is that it is non-transferable. Meaning, once it's activated it is tied to the computer that it is activated on, changing machines means changing licenses. Keep in mind, this is also the official story with XP OEM, and as I'm sure a lot of us are aware: as long as you're willing to spend 6 minutes on the phone they'll pretty much activate any XP key.
But, people have said MS is going to clamp-down on this, so what happens in the future is unknown.
I actually bought an already activated copy of Vista Home Premium
OEM on eBay (for $35 including shipping by the way). Installed it on a friend's computer, internet activation didn't work but phone activation did (took 6 minutes, 21 seconds if I remember right). Now he has a full activated copy of Vista Premium for $45. Not bad at all! And it's running on a (formally absolute top-of-the-line) Alienware computer that's probably about 2.5 - 3.5 years old...).
Retail keys are different, they're transferable, or should I say: officially transferable. I think you're limited to 3 (or is it 10?) transfers per year... officially. I'm sure if you're willing to make the phone call you can transfer as much as you want...
The 3rd scenario is what MS calls "Supreme OEMs" (or something like that). In order to avoid processing... whatever, 5 million activation requests they allow the very large OEMs (Dell, HP, Sony, Toshiba, etc.) to install Vista without activating. Since I don't care about prebuilt computers I haven't done the research, but if you're going to do a hardware change on an prebuilt computer you have to find your supreme OEM activation file thing and run it again or something after your hardware mod/computer swap/switch from 32 bit to 64 bit.
**
I'm not trying to put them down exactly, I've been in the situation where I have to choose between towing the company line (for which I get paid) and telling the truth (which only gives me a sense of righteousness). I've usually chosen the route that keeps the pay checks coming.