I agree with the above posts insomuch that MD schools will not look down upon a master's degree obtained from an established academic institution. However, MD schools will be "unfriendly" to a poor academic performance while completing an SMP. And, keep in mind that every applicant applying to medical school from an SMP may need to improve their application in areas other than earning a high GPA. Thus, if multiple areas need to be improved such as retaking the MCAT in August or September, entering the application cycle late, working 20+ hours a week, etc. it will be very difficult to simultaneously achieve a high GPA while attending an SMP. But, if you can manage to complete all these tasks then you will certainly reap the benefits and will appear as good--if not better than--other SMP students who only need to improve their GPA.
Personally, I have been accepted into Georgetown's SMP for the 2010-11 academic year, and I have also interviewed at two medical schools (one IS and the other OOS) so far this year. I am currently on the alternate list at both of these schools. While receiving feedback after my IS interview, I asked how their admissions committee regarded the SMP and if I should try to improve my 31P MCAT score. They told me that there was no need to retake the MCAT--thank God--but they went on to say that those SMPers who show improvements in the average/deficient area(s) of their application will be held with a high regard (i.e. they will be "friendlier" to those SMP students). Then, I told them that I had been accepted into GTown's SMP for the upcoming academic year, and they replied by telling me that--in my case--I would greatly benefit from an SMP as long as I maintain my increasing GPA trend (I have been hovering around a 3.8 for the past 4 semesters, which has resulted in a science and cumulative GPA of ~3.44 after 7 semesters) while in the SMP as well as explain my EC's more clearly in my AMCAS application if I do not get accepted from either wait list this summer. If all goes well, I will graduate with an undergraduate science and cumulative GPA of 3.51 in May and add a few more academic awards and community service hours to my resume before beginning the SMP at GTown. Thus, medical schools will be "friendly" to SMPers who have not only maintained the strong aspects of their application, but have greatly improved upon the aspects that they regard as average/deficient.
