He looks crazy, with the enormous beard, but his appearance belies an impressive amount of sanity.

I've been really impressed by listening to him. In particular, he's very up-front about what we don't know yet, and the uncertainty involved, and he's very careful not to promise more than he can scientifically justify. This sort of thing does not come through very well in sensationalist mass-media portrayals of him, though.

I think he has a good chance of finding ways to slow down the aging process and buy us some time, just like we've managed to extend lifespans heavily through other advances in medical and related technology. However, I have very low confidence that that direction of research will manage to completely solve the problem. We have far too many ways of breaking down, and not all of them seem solvable by patching. I have somewhat more hope for a solution from the AI camp, personally. I just hope the Uncomfortable Truths Well (http://xkcd.com/568/) doesn't prove correct.