If you have 4 license keys listed on your account summary, I'd give sales a call.
I don't remember the official policy but I thought the limit was 3 before having to pay extra for installation. Basically, 3 allowed you to have it at home, at work, and a laptop.
My phone call to sales to clean up the license keys associated with my account took all of 5 minutes, and that's because I have a really old and slow computer so most of the 5 minutes was spent waiting on the machine to verify the correct site key.
I, too, am looking forward to the upcoming price wars. My computer is acting very funny lately and I don't think it has too many hours left - no matter what I do to it short of reformatting the hard drive. And even then I don't think that'll be enough. My big debate is to install WinXP, XP64, or be an early adopter of Vista on the new box.