I think this could all be political gamesmanship. In 1992, then-candidate Bill Clinton had a problem in that some white voters in swing states evidently thought he was too beholden to african american voters. Clinton's campaign advisor, James Carville, came up with a way to re-assure worried white voters. He did this by having Clinton publicly put down an african american rapper named Sister Souljah who had particularly left-wing views. The tactic worked. Clinton's poll numbers went up among southern white voters who felt more confident in him after that.

Fast forward to this year. Barack Obama, an african american, is going to be the nominee. The Obama people might be reasonably worried that the GOP in the fall will plaster the airwaves and media with images of Obama with Jesse Jackson and Al Sharpton, the two most politically divisive african american leaders. This in order to create anti-Obama sentiment among those voters, many of them jewish, who do not like Jackson or Sharpton and view them as anti-semitic. So the question Obama's people might have asked themselves is how can Obama distance himself in advance from Jackson and Sharpton? Logically they might think the best way would be by having Obama trashing Jesse or Big Al like Clinton did Sister Souljah? But that would certainly not work, it would upset other leaders in the african american community.

Is it possible therefore that they may have decided that if Obama can't trash Jesse to get his "Sister Souljah" moment, that Jesse should trash
Obama to achieve the same purpose? Maybe Jesse Jackson was contacted and arranged to make a well placed comment slamming Obama on an open mic, so it like an accident, but all the same conveys to jewish and white voters that Obama is not in Jesse's back pocket. Thus mitigating the damage that any buddy/buddy photos of Obama with Jackson or Sharpton showing up in GOP attack ads might cause. Jesse Jackson's a smart man, he might have gone along with it. Jackson's son is positioned to run for Obama's senate seat if he is elected president. So perhaps Jesse was more than willing to say those comments, taking a hit for the Obama team. A reverse Sister Souljah you might say.