I cross-posted the same question to 'questions for the team' in the faint hope liz might answer it
there.
From users that have replied having hit the limit, it looks like it really is only 2 activations in total - and reinstalling on the same PC, in a different copy of windows counts as the 2nd activation. So people going 'oh, it installed fine on my laptop too, it's no problem' are in for a nasty surprise when they come to reinstall windows.
I didn't expect getting it 3 days later (UK) to be a blessing. There is *NO WAY* two activations total is acceptable for a game. Unless we do get a damn good answer about this from 2K, my copy is going back up-opened, and I know two people personally that will do the same.
I've not subscribed to the idea that 2K is being bought off to make the 360 version better, that was just sour grapes. But the 360 version has no date limit, no activation, no resale block, and it's being pirated. I'm not even going into the SM2, mouse sensitivity or vert- issues. It looks like 2K really did decide to screw over PC gamers to pump up 360 sales. I don't own a 360, and I'm sure as hell not buying one just for bioshock.
I'm personally boycotting steam still after the half-life 2 launch debacle (12 hours to authorise and decrypt an offline retail copy with no warning), so no bioshock that way. And frankly, if the PC activation really is only 2 uses of the code ever, then 2K is definitely going on that list too.
2K Boston, you've made a great game, with a few UI niggles that can be patched. Your fear of piracy is going to lose you a *lot* of PC retail sales once word gets out that you get one reinstall of windows with bioshock, and that's it. Fix this, before it's too late.