something like this?
here is a list of other app's
I was wondering the same thing. Iphoto on the Mac lets you do it (doubtful the Ipad does, right? I can't even think how it would - two finger tap?) so I don't know why Apple would be opposed to it. I think it's just that no one's created an app that accesses the data yet. It's not something I'd use a lot, but it could be handy to have at times. Someone get on this!
This thread is almost 2 years old... I'm sure they've found what they're looking for by now (or have long given up the search).