I have been playing this since it came out on Oct 21, these are my impressions.
You can't take this game for any historical value, let's just get that out of the way now. However, don't let that ruin your view of this game. If you want historical WW1, play Verdun.
Overall I am having a blast in this game, I have not had this much fun with cursing since Battlefield 1942. I'd put the gameplay of this game somewhere between Battlefield Bad Company (1-2) and Battlefield 2, more towards Bad Company though. The graphics are top notch, no complaints there. Sound design and quality is AAA. Have come across only a couple of bugs, so not bad.
The main single player campaign is fun, but short. Who plays single player in BF anyways. I definitely recommend this game to anyone that likes FPS, BF, or multiplayer team games. With hardcore mode on the horizon, it's only going to get better.