Matching the first choice is matching isn't it.
To the origional poster, I work in a predominantly MD medical complex and college, there are a few DO's, I have spoken to them and they indicate that they had no problem finding a residency that they were interested in. I comes down to who you are not where you went to school. Are there still some MD's who dont think highly of DO's, the answer is yes, just like there are DO's who don't like MD's. My advice is let your actions speak for you rather than the initials after your name.
Side Note: The pediatric critical care residency at Childrens hospital of Wisconsin, which is one of the better programs in this particular sub-specialty has two positions each year for residents (MD program), and there are currently two DO's doing the residency, thats 2 out of six, because I believe it is a three year program. Not a bad ratio if I were to say so. I don't think that they are here because they are DO's or MD's it is because of how good a doctor that the person is.
The typical premed comparisons between DOs and MDs are just that a premed curiosity, in the real world of medicine you are judged based on your abilities.