IMO, what third-party libraries are included with the Windows and OS X binary installers, what versions of them, and when to update them are questions without firm established policy answers, say in a PEP.  In many ways, for the installers we are performing the role of a third-party distributor / integrator.  In many other such situations, the third-party libraries would be dynamically linked from the platform OS's or distributor's version and would be independently updated, assuming ABI compatibility is maintained.  For the python.org installers, I think the updating has been mostly at the discretion of the installer developers with occasional instigation by the release managers or other core developers in the cases of security issues.  FWIW, the most recent 2.7.x installers for OS X ship with SQLite 3.8.3.1.  The current version of SQLite is 3.8.5 and that project has a very good reputation for its well-tested, regression-free releases.  So I would not see a problem in upgrading the library but I would get a pronouncement from the release manager.