Deliberate mistake: When Max and 99 are in the air, they can be seen talking to each other. This is not possible (as proven on Mythbusters) even if you were yelling at the top of your lungs. The wind would make any noise unrecognizable, yet we hear them talking to each other just fine.
Get Smart (2008)
1 deliberate mistake - chronological order
Starring: Dwayne Johnson, Steve Carell, Anne Hathaway, Alan Arkin, James Caan
Continuity mistake: When Max and 99 are fighting Dalip on top of the bakery, Dalip punches a hole in the wall beside 99's head. When he body slams Max, the hole has disappeared. (01:04:55)
More quotes from Get Smart
Trivia: At one point in the movie, when the Chief is talking to the President, the President says "nucular weapons" once or twice. Frustrated, the Chief says something to the effect of, "For the last time, it's nuclear." This is an obvious jab at President George W. Bush, who was notorious for invariably saying "nucular" instead of "nuclear" when giving speeches.