Which platform would you use for location based marketing? Foursquare or Facebook Check-in?

It has to be a facebook backed foursquare channel! Claim the location on foursquare, create a campaign to get people to check-in at our location on facebook, and celebrate the check-ins with offers and etc...
to get user engagement.
make sure the foursquare location has pics, tips and reviews to get engagements! a special treat for Mayor along with recognition for VIP hangouts will do wonders in a short time frame.

I choose Foursquare since it is more fun, people are kind of challenging each other in order to win badges.
Plus Foursquare offers you recommendations about places and many other options.