The iPhone/iTouch web interface launched yesterday, but it seems only a few shows work so far.
EDIT: Trying it out some more, it seems like a lot of show work. Only problem is it seems to be using off air recordings, rather than the original versions show on the proper iPlayer. For example, Little Britain streamed onto my PC is a clean episode, yet the iPod version has the ident at the start and the BBC Three DOG over it.
I find the interface a bit irritating. If they've gone to the effort of making the shows viewable on iPhones/iPods, it would have been cool if there was a iPhone/Ipod specific interface too. Perhaps it's coming. In the meantime, while I'm loving the fact I can watch BBC shows on my iPod, I'm finding having to zoom in and out of the page a little annoying.