Update: I was unfortunately not aware of Shamus Young's severe criticism of Fallout 3 available here to link in the original piece and I regret that. It dovetails rather nicely with what I've written and it's much better executed than my piece. I strongly recommend anyone...
Mechwarrior 3 is somewhat of a departure from the previous games. While they focused more on action, mw3 focuses on the simulation aspects of the series, even if a simulation of a 100 ton walking tank seems a little contradictory.
Mw3 improves upon the original games in a number of ways. First, and most noticeable, are the improved graphics. The mechs are leagues more detailed, buildings actually look like buildings, and weapons fire is pretty convincing. Sounds are more up-to-date, and it feels like being in a futuristic battle, not an 80's sci-fi movie. Unfortunately, the music has taken a step back. Where mechwarrior 2 had a powerful futuristic classical track, mw3 has just a couple tunes, all forgettable and none as blood-pumping as they should be.
Also improved are the game mechanics. Mw3 plays completely differently than the last games. The player can use a joystick and those controls will be familiar to fans of the series, but players also have the option of using the mouse to independently move the arms. This is difficult, as most people actually don't have three arms, but it makes the use of a keyboard/mouse control scheme a tad more effective, if a bit more dexteritously challenging. Many of the weapons have also changed, with the most noticeable difference being that lasers no longer fire projectiles, and instead have a constant beam which the player must hold on the target.
The story in this game is excellent. Mechwarrior games are known for that, and mw3 does not dissappoint. It opens with one of the best cinematics of all time and by the first mission, the player is abandoned and alone on an enemy planet. Due to the player's circumstances, briefings are illustrated by assumptions, old satellite photos, and outdated probe drops. It makes for a tense experience as the player doesn't know what to expect when they get ingame. Voice acting is well done and players seldom hear lancemates repeat statements.
The multiplayer is what one would expect, though few continue to play the game. Players team up, load up, and move out to show each other up in several gametypes such as deathmatch, team deathmatch, and destroy/protect.
The game suffers from numerous bugs when played on an xp machine. Players may find themselves floating above their enemies or walking through walls, but such bugs can be tolerated...to a point.
Mechwarrior 3 is a great game. With excellent mechanics and a superb story, it's easy to get sucked into the it. However, smaller pitfalls such as bad music and its somewhat buggy nature trip up this walking tank.