This is hands down one of the best games I have ever played.
At first I was turned off by the first-person shooter look to it. While I'm a fan of the FPS genre, I thought it was overkill and a bit trendy to make Metroid into an FPS/Adventure. "Great, they're going to ruin Metroid," was my initial thought.
I was wrong.
This game goes beyond the FPS feel and takes it to a unique level. Just imagine Super Metroid in total 3D.
The concept of the game is pretty much the same as previous Metroids in that you explore a certain area until you acquire a specific item that allows you to proceed to the next area. Of course, getting these new items means you need to re-trace your tracks because it's more than likely that you can open up new areas in already explored regions.
At some points it even has a survival horror feel to it. You'll walk into a room that's covered in fog not knowing what lurks in front of you.
The sound in this game is as pleasing to the ears as the graphics are to the eyes. It's very atmospheric and compliments the area of the game you're exploring. The only time the music will drive you absolutely insane is when you're fighting Space Pirates and it takes an obnoxious turn for the worst.
The bosses in this game are very difficult (aside from the first few "warm up" bosses) and some require a bit of thinking before you can get the first hit in. Each one is harder than the last.
I've been a fan of Metroid ever since the first one on the NES, and Metroid Prime completely lives up to its name and will no doubt get the new generation of gamers hooked on the series.