Everything would be pay-per-view, and you’d have access to an enormous achive of all shows that ever aired, and you can watch anything you want at any time, commercial-free. The prices for individual shows would be very reasonable – let’s say a dollar per half-hour show – and you can check your bill any time through the television interface  to make sure you aren’t racking up too many hours.
You could manage lists of shows you’ve already seen, shows you want to re-watch (always for free, of course), and shows you’d like to watch later. This would help you keep organized if (for instance) you want to catch up on older episodes of a show in chronological order.
There’d be lots of adult content for every kind of taste/orientation, which could be locked out with a password for concerned parents.
The news would have a definite political bias, and they would not try to hide it. There would be many news programs from many different perspectives – liberal, conservative, libertarian, centrist, athiest, socialist, Christian fundamentalist, Jewish, Muslim, etc. Nobody would claim to be objective, and the best way to get the real scoop would be to watch multiples sources and use your own brain to seperate the spin from the facts.
Definitely a “Blowing Stuff Up” show. With a huge budget. (This week… An old battleship filled with 50,000 live chickens!)
Futurama, Firefly, Angel, and Deadwood would be resurrected, along with a few other great shows that died too young.
All shows would be required to have (and use) the appropriate technical advisors. For instance, Battlestar Galactica would have a staff of full-time planetary scientists, Astrophysicists, Engineers, Biologists, and Sociologists to comb the scripts for bad science or logical inconsistancies. (“If you absolutely must use cylon-hybrid blood to cure cancer, here’s how it could be explained…”)
Everything would be offered in ultra-high resolution mega-widescreen 10.7 channel super-surround, or whatever, but it would work just fine with a cheap TV too.
It doesn’t matter if there’s religious crap, shopping channels, gardening shows, infomercials, telethons, golfing, fishing, or other borefests, because I don’t have to watch them. 
There would be more drama that focuses on long, multi-season story arcs, rather than shows that reset after each episode. This would be a natural progression from the pay-per-view system, since shows would no longer feel the need to be accessable to new viewers. Even new viewers could essentially start from the first episode and go at their own pace.