"A bird in the hand is worth two in the bush."
$6BB today invested in AAA bonds for ten years will be more than their corporate valuation after their deal hawk coupon site's novelty wears off. Eventually Facebook, Twitter or Google will create better 'hyperlocal' business models and monetize the long tail of local search with their massive reach.
Good luck bros.
b) How many companies who turn down seemingly-huge acquisition offers turn out later to be 'just' whatever they were doing at the time of the offer? Most startups at any stage don't stay fixed at doing 'just' whatever they're doing at that stage.
But... the founders, employees, and other insiders of Groupon have already been handsomely paid off. For them, the chance at several billion dollars more in a few years time is worth the risk of rejecting the Google deal.
And said bush is surrounded by a ring of fire. And explosives. And zero humidity.
Regardless, we don't have all of the data - hard to tell from outside