Although a Mass Effect 2 designer said back in June there would be "no new game plus" - a second playthrough with abilities and items earned from the first - BioWare's community coordinator has said rather definitively there will be.
On Thursday, BioWare's Chris Priestly wrote the following:
If players start a New Game + after beating the game they will be able to re-use the same character import file they did for their first playthrough. Yes New Game + is making a return to Mass Effect 2!
But on June 27, Preston Watamaniuk, the lead designer for the original Mass Effect, said "New Game Plus" was too problematic to be included:
The reason is progression. We have been working very hard to make sure we design the abilities system to offer smooth progression into ME3 from ME2. Allowing double progression on characters makes that almost impossible. We replaced that feature with playing after you were done because it preserves progression and allows for smoother downloading of PRC.
This is hard to reconcile having not played Mass Effect 2, of course, and myself having not completed the original (I've also not finished Catch-22, The Great Gatsby and other significant works of literature. It happens, you know.) Watamaniuk's statement did not preclude "playing after you were done," but that is a completely different thing. I'd be inclined to say Priestly misspoke, but he clearly says "New Game + is making a return to Mass Effect 2." I've reached out to him for a clarification.
Let's not minimize the info contained in the rest of Priestly's post, which discusses how characters imported from the first Mass Effect will work in the sequel. Priestly reminds that the import will "carry over all your decisions and plot decisions from ME1 into ME2." That means the story path you face in Mass Effect 2 will conform to what you did in the first game. "We don't want to list everything out and spoil the surprises we have in store for you, but rest assured you will be pleased when you see just how much carries over into Mass Effect 2," he writes.
From a gameplay standpoint, while you won't be playing at the same level as you finished Mass Effect 1, you will see perks and bonuses commensurate with where you finished the first game. "Ex, if you finished ME1 as a level 35 character, you will receive a bonus, but if you finished ME1 as a level 50 character, your bonus will be larger. That being said these bonuses will not put new playthrough characters at a severe disadvantage."
Saved Games, Importing Information, Bonuses and New Game + [Mass Effect Forums]