Well, right off the bat, this is the only game that really choked me up a bit in the part!
The game's graphics are powered by the Unreal 3 Engine, so it will pretty much run on most systems and still looking pretty damn good. The only qualm I have is that, aside from the main missions which have varying environments, the side missions look all pretty much the same. For some reason all the planets you visit are hectically mountainous (thank goodness for your ATV), and they all have practically the exact activities on them. The only major difference being the "terrain". The "warehouses" on some of the worlds all look exactly the same aside from a box or two in different places, and different walll textures. There isn't a mass variety of enemies either!
The sound is top shelf stuff though. The soundtrack is amazing - especially the music playing in the background after the abovementioned part when you loose a colleague or two - and the voice acting is pretty much well done.
Gameplay is simple and engrossing, especially the HUD when you push SPACEBAR.
The crux of the review is that it will not be the graphics, sound or gameplay that sucks you in - it will without a doubt be the STORYLINE. The characters are so well thought out that you kinda miss them when you finish the game. You tend to wish they were real so that you could learn more about them, and spend more time with them. The story pulls at the heart strings a bit, and you might even land up feeling sorry for the "bad guy"!
I would like to think Mass Effect as an experiment. It was without a doubt a success, so I expect Mass Effect to be 50X more engrossing and entertaining. Pity though the main storyline is kinda short!