All this talk about neato-spiffy future hub-and-spoke supernodes-and-leaves architecture is great.
But I was kinda thinking of first solving the problem that anybody who just wants to download the client, get a few coins from a friend, and then spend them on something has to wait a very long time right now. That doesn't require any re-architecting of the system or any new networking messages, and should make the "out of the box" bitcoin experience much better for lots of people.
And it is a step towards a future neato-spiffy Uber-efficient hyper++client.