Dual Booting Windows Vista Ultimate 32 and 64 Bit... CD Key?

'lo... apologies if this has been answered already... however...

Reading the recent article "Vista Workshop : More RAM, More Speed"... it mentioned that your 32-bit Vista cd-key will work for your 64-Bit Vista copy. Assuming this is true...

Does that mean I can load 32-bit Vista and 64-Bit Vista onto a single computer and run them on the same CD-Key? Further, has anyone here done this, and if so, has it run without a hitch (i.e. not encountering "CD-Key already registered" issues)?

I ask this because I participated in the Windows Feedback Panel, and I was sent Windows Vista Ultimate 32-bit and 64-bit... and funny enough, each DVD came with a different cd-key, so naturally... it made me curious .

I would have tested this myself, but I haven't built the computer that I will be loading these onto yet.

Thanks for your replies!

Excellent. Legal is good then.

Now... for practical... has anyone done this before, and if so, have they run into validation problems or triggered some sort of anti-piracy measure because of it?

I'd take the word of the aforementioned article... but considering how it was inaccurate on a couple points, I wanted to verify with someone else.