The new version (CMx2 engine) has much better graphics, and is detailed down to the individual soldier. The terrain modeling is also much improved, though there is still a bit of a "hex effect" in the layout, which is pretty much unavoidable in this type of game. There is a lot less abstraction, ballistics is even modeled down to the the individual rounds. I also like that you have a choice between playing in "real time" or turn-based (the "wego" system where both sides resolve their orders in real time, for one minute, then the game pauses to await new orders). I played the demo for the older version using the CMx1 engine (Afrika Korps) and I would recommend the new version.
Be aware, though, there can be quite a bit of a learning curve, not only for the controls, but tactics as well, as this is very seriously based on r/l. It is a game, and not a simulation, but it is definitely not an arcade game. Sort of like comparing AH2 to an arcade shooter. The community has been great, I have been able to ask questions and get good answers, often within minutes, and while there is a bit of good natured banter here and there, I haven't seen any flaming or other foolishness.
I haven't played this type of game in a long time, but was a fan of the Talonsoft Campaign series. Definitely try out the demo, the new version is "Combat Mission: Beyond Normandy". I have my pre-order in
