Great idea for a thread.. I'm always trying to find new series I haven't seen yet
The first major show I would add to your list is, of course, "24".. Season 1-3 are amazing.. If you haven't seen it, put them at the top of your list. You will get similar feedback from others on the forum about 24, you just can't beat the early seasons.
The second show I would add to your list is "Prison Break". It is only one season in and it started out relatively slow, but it definitely fired up to become a great series. It's not as good as 24, but I'm pumped to watch the next season..
The third show I would add to your list is "House M.D".. If you enjoy sarcastic humour House is definitely the show to catch.. You don't have to watch it like other seasons (from ep 1 to the finale) but it's good show to throw on if you want a laugh (plus Dr. Cameron is hot).. I would add this to the end of your list, it's a good show to watch every once in a while, but it does get repetitive. Hugh Laurie's sarcastic comedy is well worth it though.. Don't leave it out!
Since it looks like you are on an HBO kick (Deadwood/Wire are both awesome), you should pick up "Band of Brothers" (if you haven't already seen it).. BoB ranks as my favourite HBO mini series ever released.. The characters are so real and well portrayed, I can't say enough good things about BoB..
If you enjoy Speilberg (BoB) you should also check out "Taken". It's not as good as BoB, but it's a solid mini series!
I'm looking forward to find other recomendations.. I haven't watched much since summer started.. I usually keep the show saved up until the winter hits up in Canada lol