I mostly agree with Bob's three points, although for me (a) is not that important. I mainly use it to call win32 apis, and I gave up to wrap windows header files automatically, after some experiments (I got most far parsing header files with Simon Burton's cdecl.py module). Automatic wrapping may be more sucessful for simpler header files, if someone wants to work on this and submit code I'm open.
The ctypes.com package imo shows the real power of ctypes. And I don't want to fire up the C compiler for each and every new com interface I have to use. (Has anyone used pyrex to use com interfaces?)