I have to hand it to President Obama for doing this. I don't know the history of such events, but a televised Q&A session with the Republicans has to be a bit nerve racking.
He did well in defending his positions, however, I think his attacks on Health Care proposals from the right being "impossible to realize" are a bit goofy. The proposal from the left is just as "impossible to realize" and that is why nothing close to what either side has proposed will come to pass.
I like him for doing things like this though, it's definitely something that would have been a comedy reel on SNL if Bush had done it at different points in his career.