The second I saw this I was completely stunned how well this is. The background reminds me of Phazon, it has this nice blue tone as well as all those little details that almost make me hear the sound when you get too close to Phazon. Also the red eyes in the background add a nice, eerie feeling. (: Samus herself is also very well drawn, from the pose (she is scanning something, right?) to all the little details on the Varia Suit; like the little scratches, they show that she's been in battle before. What I also like are the lights, especially on the legs. they really shine at the darker areas. But there's one little thing that bugs me: the red part of her chest is a little too "flat" - it's usually a little bigger. But it doesn't stand out too much. The coloring is very nice. The metal looks really like metal and the shadows are nice as well! Well...except for that bottom left corner where Samus' foot seems to merge with the background - but that's just another tiny little thing.
Overall, I really like this, it's a great piece of artwork! (: Great Job!