I have heard of it as the home of Sports Jeopardy but I also saw it as an app on my new smart TV.
Is it as good as they claim? How do they support themselves?
I have the app on my PS3.
The few things I've watched were definitely not HD, but weren't worse than normal 480. They had commercials, just like in broadcast TV, except I recall them being placed in a more mechanically regular fashion, which annoyed me more than a little. But I was watching a couple of movies, not a commercial TV show; maybe they'd be slotted into the proper commercial breaks.
Like broadcast commercial TV, it's free for you (assuming you've paid for the hardware to work it of course); they sell advertising.