The immediate focus should be on neither the 2012 presidential race nor the 2010 Congressional race.
There are bigger fish to fry.
2010 is a census year. That means, it is also a re-districting year. The immediate goal has to be on capturing as many state assemblies and governorships as possible. To the victors of 2010 go the spoils, and the spoils are the rights to draw state congressional districts to the greatest partisan advantage. You might find this unseemly, but the fact is, the Democrats will do it in the states they win and we better be prepared to do the same.
The bulk of our energies the next two years should go toward building state house majorities. That will pay longer term benefits down the road in recapturing the Congress and White House by (a) ensuring fair district drawing and (b) electing the next cohort of leaders who will one day advance to the national stage.
To paraphrase an old lefty battlecry: Think nationally, act locally!