Apparently, the iTV will have a small hard drive to serve as sort of a cache to save movies so you aren't constantly transferring them over wireless signal.
Disney's CEO let this slip in a conference with Goldman Sachs in addition to some other thoughts about selling content for this system. You can read about it in Electronista.
It makes you think about how closely Disney, Apple, and Google are getting these days...
(Thanks to MacNN for picking this up...)