Many people (myself included) have said that people won't watch television on a 2-1/2-in. screen, such as the one of a mobile handset. That's now being put to the test (sort of) with Apple's latest iPod announcement. While the device is an audio player first, it offers the same type of display that the handset makers could easily provide.
Apple's plan is to sell downloads of TV shows just like they do music. If it does prove successful, you can bet that the phone guys will be lining up right behind to get their piece of the pie.
The real money comes when the service provide can supply the bandwidth to download the programs (and music) over the cellular network, rather than having to go through the process with the PC. I wish I could say that it's right around the corner, but history says otherwise.