Foursquare just posted its promised mobile app overhaul this morning, and it's a doozy: virtually everything in 5.0 has been given a fresh look or, in some cases, a complete rethink. The changes are, ideally, to goad us into using Foursquare to find places to visit, not just to check in after we're already past the front door. But is Foursquare pushing too hard? Will mayors want to resign in protest? We're digging in to find out. Gallery: Foursquare 5.0 hands-on