I got some more information about that call.
It was a live call last night around 7 p.m., not a robocall. The woman on the phone identified herself as with a polling firm of some sort, but did not indicate that she was working at the behest of either campaign.
The call was 6 or 7 minutes long and started with "Are you a registered Democrat?"
After that question, the caller asked, "How closely have you been following the Rev. Wright story," to which the voter could answer "Very closely," "Somewhat Closely," and "Not Closely at all."
The next question was, "How has your view of Obama been affected by this story," to which the voter could answer along the lines of, "It's the same," "It's somewhat more negative," "It's somewhat more positive."
The caller read two statements from Hillary and Obama from the trail and asked which the voter agreed with.
The last question was, "Are you leaning toward voting for Obama or Hillary on Tuesday."
All of these questions are best approximations based on talking to one person who got the call last night.
Update: Ben Smith has word from Obama and Clinton spokespeople who say the poll didn't come from either camp.