I dont think that just taking upper level classes will cut it. I would talk to the admissions director at every school to you applied to and ask them for guidance on how to proceed. At this point, it cannot hurt. Just call/email/snail mail them until they agree to meet with you. I think a lot of them will not be overly enthusiastic at reevaluating your application with only upper division sciences.
In any case, reapplying this summer for 2007 matriculation is a bad idea. Your application will be no different than it is now. You should take the remainder of this semester and even the summer to study for the MCAT, and also work on your EC's this summer. Then dive into classes in the Fall (whether at undergrad level or an SMP), reapply in 2007 for entry in 2008.
If I were you, I would send out applications to all the SMP programs *right now*. Classes fill up quickly once people realize they will not be accepted anywhere. Fortunately for you, this realization occured early. Apply to Georgetown, BU, Drexel, EVMS and even RFU. If you decide later that the SMP is the way to go, you wont have to sweat for a seat once classes fill up. Its just a good safety idea.