Straight to the point. If you haven't played the first Mass Effect then you can completely Dismiss these points and may skip to the next paragraph. I LOVED Mass Effect 1. I Believe i racked up a good 70 hour save file on one profile. Every aspect about Mass Effect 1, Personally, was amazing. So i was frustrated that everything I loved about Mass Effect 1 has been taken out of Mass effect 2. What the Hell! No longer can you do jumps in the Mako on any planet you fancy whilst battling Gigantic Worms. Or take out an outpost in the Mako. Or search for resources using the mako. Gone are the many attribute points in which you can assign power ups to. No longer can you add powerups to your armour, Wepons and grenades. All of these separated this RPG from others. All for me were just loved features of the first. What I was hoping they would keep.
However if you've never played the game then this game will blow you away. Story telling is awesome. The story itself is better. There is a huge diversity in the gameplay. The graphics are epic. The combat has been significantly improved. Personally the combat was a feature that gave its predecessor some character.
This is an excellent game. But DON't expect it to be like the first. The only similarities is the universe in which Mass Effect lies. Everything else has been stripped out and revamped. That said not everyone liked the features that I enjoyed in Mass Effect 1. So for many it was a massive improvement.