WOW, at last, a great military sim.
If you an FPS nut like me the game is worth buying. Whether you will enjoy it is another matter. If you like all the aspects of a game like CoD you may not enjoy this as much. Starting a game, online or single player, may see you making your way across thousands of meters of brilliantly modelled landscape before you even engage in a battle. This is from some view points a bad thing, again, if you like instant action ARAM2 isn't the game for you.
But talking about the landscapes, wow, they look great. I'm playing with the 1.2 patch which has disabled anti aliasing but it's still looking sweet. I've got an E8400 running at 4GHz, 4GB RAM & nVidia GTX285 and everything is set to full with a fairly high view distance. The game is visually brilliant and its running a good engine, so even older PCs should run the game ok.
The single player campaign is a little frustrating, but this comes from the fact it is completely open, and the lack of guidance can result in you running around for a while until you stumble upon the right area (if you don't listen). However, this openness results in a new style of game which will give you hours of fun and re-playability.
Multiplayer – hmm, perhaps a little early to comment, there aren't, from what I can see, any proper dedicated servers out there. The released version of the server is still in beta stage so hopefully we can expect great things when everything's sorted out.
Overall, a brilliant game that looks dare I say it, "as close to real life as I have seen yet", apart from out the window. It is certainly fresh looking and not just "another FPS" for your collection.