1. Idle Thumbs - I doubt I can add anything that hasn't been mentioned, but Idle Thumbs is pretty much my favorite podcast ever (with maybe an exception for CGW/GFW). They been more focused than usual since coming back and I am not entirely sure what I think about that yet. Either way, it is still the only podcast I listen to every week.
2. Watch Out For Fireballs! - I learned about this podcast from Something Awful (since the guys who run it are members there). It is sort of like a book club where they chose a single game and just focus the entire episode discussing it. I don't listen to every episode due to time, but I have enjoyed the ones when I have listened.
3. Giant Bombcast - I like the Bombcast for their crazy off topic discussion more than anything else. My taste in games is so different that their discussions don't really help me much, with the exception of Dave or Drew being on the cast.
Edit - I can't believe I forgot about Three Moves Ahead. I would put that at number 3, instead of Bombcast. Again, I don't usually have time to listen to it on a regular occasion, but I love it when I can. Especially if Tom and Bruce are on.