Also, personally I think, no matter what happens, if the cat goes to the kennel or if a pet sitter comes. Tell your cat whats going to happen ahead of time, and that you will come back.

If the cat goes to the kennel, let him sleep with a shirt that you have warn *unwashed* for a while. So that he can keep your familure scent with him.

As for someone comign to your house, ask if they will leave an article of clothign they have warn at your house for a couple days before you leaving, so that they will associate the pet sitters scent as something to do with home, and that it's positive.