If you want a roleplaying experience, Mass Effect is for you.
The game places you as a character with the name Commander Shepard - you select your gender and first name, but your first name is never spoken. It begins with a covert pickup of an ancient artifact on a prosperous human colony on the planet Eden Prime, and throws Shepard into an adventure of stopping the Milky Way Galaxy from utter annhilation.
In a nutshell, this game provides a deep and interesting roleplay experience. There are also many worlds to explore and extracirrucular activities such as gambling, collecting minerals, miscellaneous items, and there is even a tiny bit of dancing. You know a game is good if your character can save the galaxy and lay down their dance moves in the same day.
The graphics are stellar. The planets, solar systems, and star clusters are absolutely beautiful. The characters look wonderful in this game, and there is a lot of eye candy. Although not the best graphics I've ever seen, they are in no way second-rate.
The sound is pretty good - there are very good sound effects, the soundtrack is very science-fiction-esque, and the voice acting is not half bad. They have some excellent voice actors, and Keith David doing the voice of Captain Anderson - Keith David is my favorite voice actor, so if he does a voice in a game, I will probably play it. Although, some sounds are recycled and could get annoying to some players.
The game isn't way too difficult or very long at all. The difficulty level can be increased and you will have some trouble, but if your character is a high level and has good equipment, you can play through the lackeys, whereas boss fights or larger enemies pose more threats. I managed 25 hours after spending all my time completing the most sidequests I could, exploring all the worlds, getting the Completionist Award, and then completing the main storyline. However, it has a lot of replay value, depending on how you play.
My only list of greivances is some rather ambiguous speaking choices - there seems to only be informational, persuation, good, neutral, or hostile choices to speak towards people. I may want to say one thing or do one thing, but some minor differences don't allow me. This is a minor issue, however, and would only bother someone as precise and anal retentive as myself. I also wish the game was a lot longer, and had more plot-changing choices which would increase the replay value tenfold. I found myself wanting to explore more worlds, and I found a lot of the worlds rather linear.
The combat is satisfying but can get repetitive. You can be tactical, using your squad to supress the enemy or flank the enemy, or you can flat-out rush your foes.
Overall, I loved this game, and I plan on replaying it over and over until I get totally sick of it, or Mass Effect 2 is released. I only hope Bioware improves on their sequel, and does not make a bad continuiation of the series.