My butt... Xcode 4.3.2 is NOT stable. It repeatedly crashes when a 5.1 device is connected, especially if you try to open the organizer window. 4.3.1 does not eventhough it does not have the 5.1 SDKs. I've seen this on 3 different (and current) Macs in the past few days, so it isn't a unique situation.