Bob and Emily say that clocks have been set back one hour for Daylight Savings Time. This episode was broadcast in the spring, so clocks have been set one hour forward. - (Add'l comment) Although the original comment would be accurate if the show followed a linear sequence, the show often times skipped forward months at a time and aired episodes out of season. So the original comment wouldn't necessarily be true.
Howard enters Bob's office and says it's the first time he has been in Bob's office, but that is incorrect. In the very first episode Howard is brought into Bob's office to address his fear of flying group.
When Bob finds out Emily set Howard's sister up on a blind date with Jerry, he says he doesn't believe in blind dates and doesn't think they work. It's strange since it was previously revealed that Bob and Emily met on a blind date. However, Bob did mention that he had heard of only two blind dates that actually worked.