They're definitely gaining ground. What are the big HBO shows these days?
Boardwalk Empire
Game of Thrones
...what else? I know they've got Treme, but while it's a solid show no one watches it. I must be missing something else but just can't think of what it could be. Oh, True Blood, which I used to watch but gave up on because it got more ridiculous than I ever thought possible.
Showtime has Dexter, which is ending after next season, and Homeland, which is exceptional.
You know what other cable channel is challenging to be one of the best out there? FX.
Justified is one of the best shows on TV.
Sons of Anarchy, while I've never watched it, I've heard good things about.
They are also starting to dominate comedy with Louie, It's Always Sunny in Philadelphia, and The League (which is getting better and better).
I've also heard good things about American Horror Story.