A media pool report on Barack Obama's Daily Show taping indicated he handled the appearance with his usual calm rationality and didn't blow everything with an ill-advised gaffe, as nervous nellies (or anyone who has tracked Democratic presidential nominees for the past, oh, two decades) might worry he would. According to the Daily News' Mike McAuliff, the candidate (wisely!) wouldn't even indulge a joke about old people in Florida:

[Stewart:] "I know Florida.. Many of my people go there to retire…You might want to hold the rally early. They don’t like to miss their shows at night or the early bird special at the diner.
"No comment on that Jon. I’m trying to win Florida," Obama responded.
Stewart asked "If you do win, is that a mandate for socialism?" and asked about a range of other, mostly outlandish, negative claims about Obama had had an impact.
“It just hasn’t. I think that there’s a certain segment of hardcore Sean Hannity fans that probably wouldn’t want to go have a beer with me," Obama said.