CBS.com will sell Survivor episodes
CBS has not come out and said they won't try and strike a deal with iTunes but for the time being it seems like they're trying to avoid teaming up with the download juggernaut. They have deals in place with Google Video (you can get CSI: episodes from there) as well as Comcast's on-demand service. CBS has not instituted a "pay for it and you own it" system like iTunes though. After your purchase a Survivor episode, you'll be able to watch it for 24 hours and that's it; just like pay-per-view.
I'm not sure what the big deal is there... why not just let consumers keep the video?