Seems like the July issue of OXM magazine had some tasty morsels of information on Mass Effect 2 that were set to be released at E3, but have, miraculously and wonderously, been leaked onto the Internets through website NeoGaf.
Before we get to the Mass Effect 2 stuff, there was one thing about the first game: one more big DLC is apparently coming before the sequel.
It seems in Mass Effect 2, you do play Shepard, but there may be parts or segments of the game -- or perhaps an option given to the player -- of playing the game as different main character. Or playing without Shepard in your party. In addition:
There is a new species called the Drell, and the secondary races from the first game, such as the Volus and Elcor, will be gaining greater focus and backstory.One of the new dudes who can join your party is an assassain named Thane.Again there will be the real chance that if you make the wrong moves, some of your major characters, such as Garrus, could get zapped by space lasers.Planets: There will be a Krogan planet and Illium, an Asari planet, that is like Coruscant from SW. Also there is “Omega” with is like an anti-Citadel in that it’s huge and the bottom of the barrel, whereas the Citadel is the height of civilization. A Cerebus mothership is expected to act as a location of significance.Storyline: The ultimate story is still civilization fending off the Reapers, but this chapter will deal with this Cerebus corporation and it’s enigmatic leader. There are human civilizations disappearing and it’s up to Shepard to investigate, it’s termed as a “suicide mission” which may lead to the details of the teaser.New vehicle that controls better than the Mako…a “new” control scheme.Totally revamped inventory system Elevator system revamped where you will get the sense of scope of where you’re at and where you’re traveling.No more texture pop-in.Also on the story, they’re super-hyping the ending, saying that it’s much more grand meaningful in ME2.More weapons, more species, more/new team members.Returning team members, locations, weapons.These are rumors that can't be validated for another little while -- but as someone who played Mass Effect and is a big BioWare fan, they sound all reasonable to me and seem like the real deal.