I believe only ST 2 on OS X relies on the system python - 2.6 or whatever python happens to be in the path. Sublime 3 ships with python 3.3 on all platforms.
edit:
If you are asking about the Floobits plugin, ST 2 on OS X shells out to the system python (because of SSL).
I added a comment on this page that Package Control patches the select issue on ST2 for Windows (and explains it a little), plus includes shims for _ssl on Linux with details about how it works.
Importing select works in Sublime Text 3 on Windows. Unfortunately, many people still use ST2, since it's the default download on the Sublime Text website. It would make my life much easier if ST3 came out of beta.
Surely if they are devs they know they're not bound to the "default download".
I've been using ST3 dev builds for what, 2 years now? Rock solid all this time on OS X (with around 10 plugins). Only had one issue (high cpu load on search IIRC), that was corrected by going back to the ST3 beta for the 2-3 days it took for it to be fixed.
I'm in the same boat. I use ST3 as my primary editor and it's been quite stable.
The ST2 users are part of a significant chunk of developers who just use defaults. They use the default shell, default themes, default mail/calendar/IM client, etc. They don't toolsmith. Their motto is, "If it ain't broke, don't fix it."
Considering the annoyance of dealing with unstable software, I can't blame them... much.
edit:
If you are asking about the Floobits plugin, ST 2 on OS X shells out to the system python (because of SSL).