From my experiences on the road, interviewing in all sections of the country for MedPeds (Cali, Texas, the midwest, NC, and the NE), my thoughts
Most (if not all) MedPeds programs rotate every 3-4 months between specialties over the course of 4 years. I dont know of any programs (of the eighty or so out there) that have 2 years of one then 2 years of the other.
80% is too high a number. More MedPeds graduates seem to be either going into a subspecialty of some sort or are doing international work, but PC is still a big part of the employment demographic. I'm at a loss for a specific number as i'm not with any of my interview data at the moment.
I never heard mention of anyone leaving a program for one side or the other, but i suppose it could happen. I never dared to ask, seems like a question that if asked incorrectly on an interview could get you on the defensive about how committed you are to MedPeds as a career...
In my opinion, MedPeds is competitive for spots. 2007 MedPeds had about 10% the total number of spots that categorical medicine had, and many of the institutions were around 4 PGY-1 positions per year. It is not as competitive as say Uro, Derm or the like with limited spots and average mean Step One board scores in the low 240s and other competitive features. It is competitive as you realize that there is, for instance, one program in new york city & 4 in the state of California, which is considerably smaller that the number of individual Peds or IM programs in those areas. So, If you are dead set on doing residency in a specific area or program, you should realize this fact...
Some States courtesy of NRMP ::
For US Seniors who matched
2007 MedPeds applicants mean USMLE Step1 scores were 221 (Medicine 222, peds 217)
IM and Peds had a higher mean number of abstracts/presentations versus MedPeds 2.2/1.7/1.3
and while MedPeds had a higher number of seniors with advanced degrees (13.1 versus 10.6 & 8.3) a higher percentage of either IM or Pediatrics had a PhD degree (1.5 versus 3.4 and 5.8)
For all the data check out these links from last years match.
http://www.nrmp.org/data/resultsanddata2007.pdf
http://www.nrmp.org/data/chartingoutcomes2007.pdf
Your goal is to establish a resume of someone who is sincerely interested in the things that MedPeds has to offer and convey that information to the places you apply, just as you would for IM or peds or any other area for that matter.
feel free to add to my post fellow interviewees from this past year.