I agree how much they paid is important in evaluating the purchase (the less they paid, the more justifiable it'd be to buy it just for some talent and in the off chance some of the ideas/tech/IP turned out to be useful). But I doubt it's anything as low as $200k, because they had VC funding of a few million, and presumably the VCs wouldn't sign off on selling for a loss. This article estimates $40m, though they may have just pulled that number out of thin air: http://thenextweb.com/google/2010/05/02/google-purchases-bum...
If it would take them 3 engineers and a year to build bumptop and they paid $200,000 for it, then everyone wins.