Right, and on your last point, that's almost exactly what the NFC industry has been trying to do for years. Most successful mobile ticketing deployments seem to use the barcode-a-like on a screen approach thanks to NFC not really getting very far. It will be curious to see if Apple manage to get any traction here.

Obviously flesh blood is a good thing, however, this problem space has been thoroughly explored.

The real unexplored area is that few people have noticed just how insanely powerful the GPUs in these devices are, but again the problem is in working out what they might be useful for, especially given the trend is for mobile "apps" to really be trivial front ends for web services.