There are numerous treads on this, but to sum up. Some people have low opinions of DOs, most do not. Some states only allow DOs to practice after doing an internship, but that generally does not effect residents.
I know of many programs outside of California that take D.O.'s; in the new york area, I know that NYU, Cornell, Mount Sinai, and Albert Einstein have taken D.O.'s---feel free to PM me if you have any questions.
There are numerous treads on this, but to sum up. Some people have low opinions of DOs, most do not. Some states only allow DOs to practice after doing an internship, but that generally does not effect residents.