I know I'm premature to be discussing specialties, since I am only applying to med school this summer. But I want to make sure that the path that I am going down is the correct one.
I'm going to present my understanding of the DO vs MD facts as a set of propositions that you all can confirm to deny.
Prop 1) MD schools are slightly more selective that DO schools.
A quick lookover of
http://www.eduers.com/mcat/Average_MCAT_Scores.htm shows that the DO schools tend to cluster toward the bottom of the list. The highest Osteopathic is Texas COM at 27.3, while the lowest MD school is Howard at 24.6. The highest Med school is Washington @St Louis - 37.5. Most allopathic schools average MCAT's at around 29-32, while the DO's hover around 26-29. Not a huge difference, but a difference.
Prop 2) MD's have a better chance of getting MD residencies than DO's do.
This is shown by the differences between the match rates for MD's and DO's in the AOA figures (which I don't have and can't find right now). But there is a significant, although not overwhelming, difference
Prop 3) DO's who do compete in the AOA have a not inconsiderable chance of matching.
Prop 4) DO's do not have to take USMLE as well as the COMLEX in order to compete for MD residencies, but it can improve their chances to match into some residencies
Prop 5) DO's get a second bite at the apple if they do not match in the AOA competition. They can compete for DO-only residencies
Prop 6) There is a more limited selection of DO residencies and DO's are more likely to practice in the less competitive specialties.
If these propositions are true, then here is my concusion.
I, as a person, have a given amount ability and talent which I can and will dedicate to whichever school accepts me and that I attend. The education at any quality school will prepare me similarly for medical practice. Any residency that I match too (should I graduate and match) will depend on my good-looks, glad-handing, speaking ability, educational attainments, and test scores (not necessarily in that order

).
Therefore, as long as I attend a quality school. My residency will be SOMEWHAT affected by the school that I attend, but GREATLY affected by the amount of ability, dedication, and effort that I put into my own education. Therefore, the school that best fits my personality, life-situation, and finances, is the one that I should desire to attend.