Mass Effect 2 is a non Linear Story beyond any thing before it!
Mass Effect 2 has all these things but improved 100 fold. The graphics have been improved and there is no longer any pop-up.
Unexplored planets are no longer barren ways lands and feature unique area's and buildings accompanied by stories set apart and in the main story line, this brings better immersion. Scanning the worlds for needed mineral supplies can be time consuming but I found it far better than the old way of looking around barren worlds with the Mako. Sadly the Mako is absent. If you did not play the first game the Mako was a tank with rocket boosters that was dropped from the Normandy. The Mako has been replaced by a shuttle that is not controllable.
The game now features mini games that are far better than the "press button at the right time" hacking segments of the old game with memory puzzles and odd monkey-rat shooting games.
I have found if you listen in on peoples conversations you can get new missions not requested of you and get involved in lots of mini stories. The largest majority of the speech interaction in this game seems to be with the crew of the Normandy, not just the main team but with the crew as well.
Loading times can be long on PC's but on the X360 if you install both discs to the Hard Drive it will be extremely fast {I tried this game on an Elite X360}.
Despite previous reports, you will be able to use more than 11 characters from ME1's save system. A genius idea that lets you continue your own story from the first game and not one linear path. I can only hope this is implemented in future games from all companies.
As I said in the title Mass Effect 2 is a non Linear Story beyond any thing before it, chose you own adventure is normally taken in it's stride, but in this game the word is no longer in the dictionary.
10/10