I don't really want to get involved with the issue of how altruistic the motives of volunteers should be-I agree with the theory that one should volunteer primarily because of a desire to help without looking for personal gain, but I also see the reality that much good work is accomplished by volunteers who have some type of external motivation. However, I do think the point that the low pay of Americorps makes it essentailly volunteering is faulty logic- federal minimum wage is only $5.15/hr, so after taxes a person working a full-time job at this rate might take home a little more than $700/month. I guess that means everybody working at Taco Bell can consider themselves to be volunteers (and most of them don't even get health insurance, which Americorps provides). I know several people with humanities B.A.'s who applied for programs like Americorps and Teach for America simply because job prospects are so terrible in this sh***y economy that a guaranteed $8-9/hr job with benefits, plus several thousand dollars towards their student loan debt, was actually fairly competetive with their other job options. Calling it a "stipend" vs. a "paycheck" is purely semantics.
I'm not saying Americorps isn't a good program, it can be a great way for people to get involved in their communities for an extended period of time. But, you do get paid for it and my impression is that adcoms will view it more like working for a non-profit than as volunteering. To answer the OP's question, this is seen as substantially less "prestigious" (in the sense of impressing adcoms with your altruism, which is what I assume the OP meant, more or less) than something like Peace Corps, which requires a much greater commitment for fewer tangible benefits, and is generally undertaken only by people with a substantial desire to give to the world and with less expectation of personal benefit. Peace Corps, after all, requires you to give up 2 years of your life to move, alone, to a (usually) third world country and devote this time to some type of community service in the area; all you get is a grand total of $6000 when you get back, and basic food, housing, and medical care at the standard of the country you are living in during your service, which is usually considerably lower than the standards in the US. Obviously, very few people would go through all of that just to impress adcoms (which is not to say that no one does, just that it's less likely).
If you have time before you apply and are looking for a worthwhile way to spend it, you really are better off getting involved with an organization (in a paid or volunteer capacity) because it interests you, not to impress adcoms. You'll be much happier and get more out of your expeiences, and this combined with your genuine passion for what you're doing will ultimately make you a stronger applicant than just going through the motions of what you think med schools are looking for.
