In the long run, African-Americans will turn out at the same rate as Whites (I think a Pew study even showed a higher turnout among them than Whites in 2008).
Obama may get a slightly lower share (~92%) among them in 2012, but could get a higher share of Whites, especially in the Upper South (MO, IN, KY, OH, WV, VA, NC and maybe Florida or even the Deep South) if the economy is growing fast by Mid-2012 and Obama had a good term overall. Let's say he wins the General Election with a 10-point margin, I could see 45% of Whites voting for him.
45% of the white vote in the South? That would give Obama at the least an Eisenhower-scale landslide, something like this:
That's hard to believe.
MS more Dem than NH and NJ, now that is something groundbreaking.