One of the greatest stories ever told. Get ready to be blown away by my new favorite game.
GRAPHICS: Amazing. The character models are entirely believable and fall into the Uncanny Valley, where they look so good that you end of liking them instead of rejecting an awkward attempt at realism. You can sense the emotion and actually take them all seriously. Lips sync perfectly to the dialogue, and the end result are conversations you can feel. The environments are pretty good looking as well, but they tend to be linear and repetitive (especially on planetary missions). While the graphics are amazing, there still is the issue of pop-up especially when loading new conversations and environments. Other than that, the game is AMAZING.
SOUND: Some of the coolest music you'll ever hear. The soundtrack is complete with heavy synthesizers and sometimes epic scores. When you explore worlds, expect a light and ambient tune to play in the background as you trek in your Mako. When you get into combat, the music takes an intense turn and you'll find yourself performing better to the sheer awesomeness. The dialogue is expertly crafted, and you'll actually find yourself drawn into conversation, a feat rarely accomplished in video games. The only issue with sound is when fighting. Combatants will frequently repeat "I'LL KILL YOU" and "I WILL DESTROY YOU" and "YOU MUST DIE" etc. etc., but it doesn't hinder the fun at all.
GAMEPLAY: The combat is a mixture of RPG and Shooter that's pure awesomeness. You'll spend your time on menus equipping your teammates with various armors, weapons, and upgrades for the two. The menus are a bit difficult at first, but as you progress through the game you'll learn to love them. Now the real fun begins: COMBAT!! The combat is fun. You'll have various weapons to switch from at will (although some classes are not good with some) to your preference. Based on your class, you can use various abilities known as Biotics and Tech, which are basically force-like and hacking powers to toy with items and foes. While hand-to-hand combat is very challenging and enjoyable, the Mako combat is ho-hum. The Mako is a pretty cool vehicle for exploration, but when in combat, targeting enemies becomes hazardous and clumsy (it's sometimes easier to run foes over =D).
STORYLINE: I'm not over-exaggerating when I tell you that this is one of the best storylines ever told in video-games or in any media form. Not only is the Milky Way such a fascinating galaxy to explore, but the characters are what makes it shine. I've never played a game that made me make some of these decisions that I made in Mass Effect. As per BioWare RPG's, dialogue options are vast and account toward your Shepherd's personality. You'll make decisions that are just so tough you'll always feel regret. You'll fall in love (quite literally sometimes ;]) with the various characters and allies, and you'll even grow to question the motives of the main villain, Saren. I'm not spoiling anything, but let's just say that you'll play it over and over again to experiment with different options. Yeah, it's that good.
OVERALL: Mild flaws don't stop this from being my new favorite video game. It proves that video games are a media format just as valid as television or movies. Play it and enjoy, my friend =D