As a US graduate, psychiatry is one of the least competitve fields. I base this statement on the fact that the match fill rate is fairly low. This means there are many open spots throughout the country. Of course, there are several competitive psychiatry residency programs throughout the country. Internal medicine programs are moderately competitive.
Decent programs can be difficult to match in, and the top programs are very competitive.
Internal medicine is not as competitive as surgery, however. With managed care there had been a trend towards more people going into primary care. This trend may be leveling off or even reversing. Time will tell. Pediatrics programs in general are about as competitive as internal medicine programs.