I don't really understand what the point of this oil debate is supposed to be. At best, it's mildly damaging as it paints him in a somewhat hypocritical view. Even conceding that, this is never going to do any real damage to his campaign, since if anybody calls him out on it, it's a very easily defended accusation via basic semantics.
So, on these grounds, all right, yeah, Obama isn't 100% squeaky clean. This is hardly damaging, though, and I see little reason to throw this out there as an accusation, or defend it for that matter, as it's a non-story.
Now, if I can remember Spin 101, and felt like defending my prince from any and all accusations, no matter how minor they might be, using creative wording, he's not in the wrong at all. He didn't take money from lobbyists, individuals are free to donate to whomever they choose without representing their company, and so on and so forth ad nauseum. Obama would never do anything wrong! The new politics of change don't welcome in the corrupt shenanigans of old Washington. Try again APF!!!