Been playing for the last few hours. Played a few maps with 1up.com's own Nick Suttner which was a lot of fun (hopefully he's a little less sour on the game now :p).
One thing I must mention is how awesome Fallen (Large) is on Breach. Feels like a spiritual successor to Enwapi, with the Terrorist base in the middle and the Seals spawning around it. Absolutely brilliant, great fun.
What are your favourite maps in the game so far? Apart from the classics.