Subnixus blog is offering a contest for a free trip to vegas. Check out post #111 for the details. He is ostensibly funding this trip from his tax refund this year. Do you know anyone who has even thought about doing their taxes yet? I know for a fact (an IRS auditor told me) that the earlier you file your taxes the more likely you are to receive a general audit. They only can audit so many returns a year and they start assigning them right away. So the point is, once they assigned all the audits for the year, any returns that come in after will not be marked for audit. So the best way to avoid it is to file an extension and submit your return AFTER 4/15.
ps- this does not preclude you from an audit for specific or "fishy" items on the return, so please don't claim your dog as a dependent.