The 8/2 issue of the WSJ carried a column entitled "Health Care When You Want It" by Web Golinkin on the "convenient care" clinic network that is developing in such places as Wal-Mart, CVS stores, and Walgreens. (From that link, you can access the WSJ article on a "free preview" basis, if you register for their 2 week free subsctiption offer.) Golinkin is the president and CEO of RediClinic, LLC, "One of the nation's largest convenient care providers, and is a director and co-founder of the Convenient Care Association."
These centers are manned by nurse practitioners, and Golinkin has this to say about the quality of such care:
Research over the past 30 years has consistently shown that the primary care provided by nurse practitioners is comparable in quality to that provided by physicians, though nurse practitioners are still required to collaborate with local physicians in most states.
I'm not sure that "comparable" means the same as "the same as", but this growing service is surely a big piece of the free market response to the health care crisis, and it may be a good one. (I would venture that "comparable" care from a nurse practitioner is better than no care from a physician.) Golinkin also writes that 97% "of the more than 4,000 RediClinic patients surveyed this year said they would recommend RediClinic to their relatives and friends."