For those who are interested, here's a link to the portion of my recent Bloggingheads appearance where Mark Schmitt and I bat around McCain's Lincoln-Douglas-style debate proposal. I think it would be a mistake for Obama to accept, which won't surprise anyone around here. Mark has more sympathy for it and makes a couple of good points in favor.
In related news, I see via Mike Allen that McCain wants to extend his freewheeling Q&A franchise to his future dealings with Congress:
McCain plans "question time" before Congress. From remarks for delivery in Ohio today: "I will ask Congress to grant me the privilege of coming before both houses to take questions, and address criticism, much the same as the Prime Minister of Great Britain appears regularly before the House of Commons."
Like the proposal to Obama, it sounds like a pretty savvy move.