I get enough TV at home, decided a while back that I wasn't interested in a Slingbox. I've seen others watch theirs from PCs or Treos, and just am not all that interested.
I probably listen to XM more than I watch TV. The only downside is that I can't get that on my iPhone either, like I could with the Sprint Treo or AT&T Blackjack or Blackberry.

The crosses we bear!