Foursquare has build a solid data business, also its data team is one of the best out there. Go on youtube and watch some of their presentations to see what is possible with their data. The issue is that they are stuck in a strategy and a founders vision, this makes it hard to totally change their business, branding etc. I still think apple should have bought them a long time ago, but it is a solid buy for Yahoo, not the foursquare part but the data side, which is worth more.