ok after playin it a bit more heres a quick review of sorts :p
for playability, it works great on my machine (2.6 ghz p4 512mb ram and 128 mb radeon9600) at high settings. one of the most beautiful games you will ever see.
gameplay reminds me of call of duty. you start off in this place, walk around, find some guns, then it gives you objectives to go to this and that on the little mini map.
so you walk around through the forests/swim to places and basically kill whatever gets in your way.
so basically if you like going through a series of objectives while having to kills tons of people, then its pretty fun. you need a good system to run it though :p
i'll have to agree with leaderz0rz who said its mainly showing off its engine, with a so so storyline and such...