I started Season 1 last week and am on Season 2 now. I knew something happened in the first episode of season 2 so I spent the entire time thinking "Oh, he's going to kill him/her" and then "Oh she's going to kill her/him".

Amazing show that's as good as anything I've seen in a long time. And the writers are the best that I've seen about using technology properly. Showing the text conversations as bubbles on screen so you can read the msg is great, Frank playing a FPS on his PS3 is huge, and having Tor described and used is remarkable in itself.
House of Cards is everything that's great about original programming and is worth the cost of Netflix by itself. I have a rule that I won't watch a show until it's had at least three seasons produced as it helps me avoid getting into a show that gets cancelled too soon. I started this series anyway and it was definitely worth it.