Well, I finished GoW3 a little while back actually, something like 2 months ago, give or take. I figured I'd still give it a jab though. Story-wise, it has it's good points and it's bad points. You finally find out why the Locust Horde attacked the humans, but you are still left hanging concerning the origins of the Locust. There are several things in the second and third game that seem to allude to a possible origin, but for some reason the good people at Epic Games decided not to develop it any further than that. Perhaps there were time or money constraints, or perhaps they simply got lazy. Who knows. I think the story that they did decide to go with has a lot of unexplored potential, but let's be honest, a lot of us probably didn't buy the game for the story as it is anyways. I will say that I was a little disappointed with some of the plot points near the end though.
What most of us probably did buy the game for was the fighting and the gore, which GoW3 gives plenty of. It still retains the same cover and run system as the second one as well as similar graphics, and adds some more enemies and weapons to the game, as well as adding in a few more characters to the story. I'll have to be honest, I would like to comment on the music, but I was too busy killing Locust to notice any. Maybe sometime later I'll play the game again and try to take note of it.
I think my favorite part of the game though, would be the new Beast mode. It's hilarious some of the things that can happen playing it with friends, and for once, you get to see things from the Locust point of view, even if that means all you really see is destruction and more destruction. The Horde mode now allows you to set up defenses such as turrets, razor wire, decoys, and a few others that I haven't unlocked yet. Each type of defense can be leveled up the more you build of that specific type of defense. For instance, the razor wire actually starts out as large caltrop-like spikes, and as you set them up more and more, you will upgrade to razor while, and eventually you will gain laser fences. The only set-back is that it takes a decent amount of cash to install and upgrade these defenses, and you only get so much cash in a round.
Overall, I enjoyed playing GoW3, but there are some points where they could have improved, most of it dealing with the story itself. As I stated earlier in this post, the story has potential, but for the most part it's left to the wayside.