Arma II looks like a mad fun game, I like what they are doing with the genre. The whole gamespace is modeled accurately after some place in the world. (I think its like 300 sq. KM in russia or something)
Check the demo out on steam.
Anno 1404, Dawn of Discovery is mad fun too, it's more fun than AoE 2-3, and looks/plays TONS better.
Here is the demo page courtesy of IGN.
I own and love DoD, and I am currently downloading Arma II demo, then I will pirate it, and if it shows MP promise, I will throw money at it. These look like some good ways to alleviate Summer boredom on these rainy days that we seem to be having all of the time.