"There’s also one thing Yelp has that Foursquare doesn’t: Venue ratings. While Foursquare offers a “tip” section, it doesn’t ask for any text on the check-in page, and tips are usually shown after another user has checked in. Yelp is for deciding where to go, and Foursquare is for telling people you got there."
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The Starbucks Across the Street: Yelp Just Made Foursquare Huge | lalawag
Let venues pay to be that “tip”. Google AdWords style. Instead of buying keywords, locations buy “geo-keys”, the highest bidder gets the spot.
via Nick Douglas