This is a new show on the SyFy channel, currently four episodes in and it is really worth a watch.
Takes place in the semi-near future when Earth has begun colonizing the solar system, and three main factions of humans have formed. The three factions are currently in a cold war with each other and it doesn't seem like much will be needed to push it over the brink.
You should seriously give this show a try, it really grabs you from the get go unlike so many shows which takes half a season to an entire season to become interesting. Kind of reminds me of a BSG style of SciFi -- Darker in tone, continuing story between episodes.
You can watch the first four episodes here:
http://www.syfy.com/theexpanse