at einstein, they told me that 1/3 of the class is "traditional", 1/3 is one year out, and 1/3 is more than one year out of school.
Considering that "traditional" applicants make up more than just 1/3 of applicant pool, there may be some merit to what cammy and redskittles are saying about extra years out. This may not apply to every school, but even in a class that isn't split that neatly, I'm sure that the number of nontrads matriculating into an entering med school class is overrepresented considering their percentage of the total applicant pool.