What's in it for Facebook? Foursquare functionality is easily copied. The brand isn't terribly strong. $100M+ is hard to stomach when I don't see any clear bene

What's in it for Facebook? Foursquare functionality is easily copied. The brand isn't terribly strong. $100M+ is hard to stomach when I don't see any clear benefit to Facebook. Yahoo! is another story, as they've taken a portfolio approach. I imagine Foursquare looks pretty good as a member of that portfolio.