The big ugly Foursquare Radar update that accompanied iOS 5 -- bringing constant location tracking and social tension to the app -- has been fixed. Mostly. Although the friend alienation problem persists, you'll no longer get buried beneath horribly annoying notifications.
Before the update, Radar would ping you with suggested checkins -- like a sandwich joint you've checked into before. Except it didn't work at all, and, at least in dense urban areas, would hurl tens upon tens of suggestions at you simultaneously. It was overload to the point of defect, and I suggested just turning it off entirely.
Now, Radar won't shout at you like some coffee shop-recommending homeless man. It's much, much less sensitive, tossing you a notification when you're near a spot on a list you follow or a place you've noted down for later. It'll also simply suggest things with reduced frequency, so you can actually read one tip before another lands on you. The social minefield's still out there (why not make that a separate option in Radar?), but it's nice to see Foursquare fix this so quickly. [Foursquare]