i.Tunes and movie rentals

Ok -- so I've been a fan of i.tunes for awhile -- well, ever since I got an iPod. Last week as I was frantically preparing to leave town, I realized i.Tunes now has movie rentals. What better to do with my time in the airport and on the airplane than to watch one of these rentals, right?

Well - wrong. So I paid and downloaded 2 movies which I've been wanting to watch for a long time (Michael Clayton and Superbad). I'm excited to sync my ipod and see them appear so I can enjoy my travel time.

It turns out that my ipod is not compatible with the rental system.

huh? They didn't warn me and in-fact I didn't figure this out until the movies didn't sync and I began reading the fine print of all the movie rental terms (of course, this is after I already purchased them). I can still watch the movies on my PC - but that defeats the whole purpose of wanting them on my ipod.

Needless-to-say, I still enjoyed my trip and listened to music in the airport/on the plane. But, really my question to Apple, who has undoubtedly made a huge profit from all the apple-ipod-iphone hype: How hard is it to create some new software so that I can watch these movies on my ipod? I won't spend another $300 on a brand new ipod just for movie rentals a couple of times per year.