We have two of them plus a Plex Media server that a buddy of mine set up for me. Between the three, I probably could get rid of cable altogether. I tried to, but their retention department cut my bill in half and we still have all the same channels that we used to.
With the Plex server, I have access to all the Daily Show episodes, Colbert Reports, and a bunch of other stuff I don't even have time for. If I ever have enough time to sit and watch, I will get a Hulu Plus account so I can watch Revolution.
One word of warning, though, Netflix streaming is NOT the same as Netflix rental. You do not have access to all the movies you do as a rental customer. Still a lot of movies, but mostly older stuff. Crackle is cool, too since it's free.
If I ever add another, I'll look into the Roku stick that's $50 with remote now. That way you can hide it behind the TV. I have a Roku 3 for one TV and an older N1000 on another. I tried splitting one between two TVs using an HDMI splitter and it does NOT work. Has to have bi-directional signal throughput.