Love the new video feature of iTunes.Why can't I add my old .avi videos I have in my Movies folder. .mov's and .mpeg's show up fine, surprising.avi don't come in, given Mac and QT relationship. What am I missing?
I am speculating here but I just don't think Apple wants anything to do with the avi wrapper. There are many reasons not to like it, some technical.
But as a work around, you can convert your movies from avi to mov with DivX Doctor II with a minimal amount of hassle. As long as quicktime supports the codec you should be able to import it no problem.
It's more or less just outdated. Here is a good Wikipedia article that breaks down its limitations. The avi wrapper still does its job but it is limited, keeps videos very basic, and better options are available, just not as widely supported.