An emotional roller coaster ride full of excitment and drama.
I don't want to do a long winded review so I'll just talk about the main thoughts I have on the game. First up is the cinematics, which are just phenominally well done. Every cut-scene in the game is blockbuster movie quality, incredibly detailed and character's movements are extremely life-like.
The in-game graphics are very impressive too, especially on the Shadow Broker's ship in the atmosphere level. Explosions, weapons fire and other effects are bright, flashy and have a real impact on screen.
I found it difficult to follow some aspects of the story at times since it requires remembering specific events that happened in ME1 so at times I was doing missions that I didn't fully understand the significance of. This game also focuses heavily on missions that require you to recruit new members. Then once they join your team, every last one of them will have some sort of "personal" issue that you ahve to talk to them about and go on another mission to resolve. It's not a bad structure but gets a little repetitive at times.
Of course the main component of ME2 is the action and it is definitely much more streamlined this time around. The developers have done a perfect job of removing all the annoying aspects of an RPG and perfected the good parts. For example, there is no real inventory management. You gain various tech whle on missions, then you "research" it back on your ship. Then on future missions you can choose your weapons loadout before each mission. The other key improvement is mapping up to 3 powers directly to controller buttons so there is very little need to pause and select powers from your power-wheel menu.
My only gripe is that there is not a huge amount of variation in level design as each area has your typical boxes for taking cover and firing from and flanking routes but it's pretty straightforward and not open-ended at all. Luckily the action is top notch and very fun. I just wish there were more vehicle missions.
The essense of Mass Effect is in the connection between the player and characters in the story. ME2 has you developing close relationships with your crew culminating in a very high stakes final mission. I won't go into details but you WILL have to make several very hard choices in the end that will result in some of your crews deaths. That is how ME2 draws you into the story and really makes you feel an emotional connection to them. Very few games made me care about loosing people like this game has.
ME2 is epic and the series is one of the best in video game history so you owe it to yourself to play this game. Don't miss out.