iTunes for Mac is only adequate for music (a.k.a. yesterday's use case), and plenty of other players work very well for music too. In comparison, most people still don't have hard disks big enough to fit their entire movie collections, which is today's new use case for iTunes, and the only current way to push movies onto new-gen Apple devices.

I have an iPhone and enjoy it, but I've only played a movie on it once or twice in the time I've owned it for this reason. This is true of most people I know with iPhones, and it will similarly be true for iPads. It's a glaring problem that Apple's doesn't seem interested in solving; they'd rather you re-purchase every DVD as a movie from their store, and then be locked in to their platform or else lose your content.