It appears the mystery as to why Facebook Connect was available, and then not available, has a little something to do with blocked API access. According to sources at All Things D, Facebook denied Apple's Ping access to the application programming interface that would allow users to search for their friends, which left them with only a few friends willing to respond to their emailed Ping requests. Normally, this kind of API access is open and doesn't require any kind of permission, but when it's being accessed numerous times at a very rapid rate (like, say, 160 million at a time), it's natural for Facebook to put a screeching halt to the requests and focus on protecting their users data.
