I don't know really, i think it's hard to predict such a thing until it starts to happen. When a simple site that sells well happens then it will probably kick start people jumping on the bandwagon. I think one of the main sites people are tending to develop atm are myspace related ones although it does seem to be carming down a bit. As you said proxy sites seem to be popping up everywhere as well, the amount of new image hosting seems to have reduced from what it was, probably due to the huge amount of them.