For what it's worth: http://www.wisdompubs.org/sites/default/files/WisdomStyleGuide201308.pdf

I've broken these rules pretty much non-stop, including capitalization.  Still seemed interesting.  Especially in contrast to the more informal style common to message boards.  Wisdom Publications is as much an authority on Buddhist editorial guidelines as any org I can think of.  They've published an broad range of texts from the myriad Buddhism(s).  

I found the sections on Tibetan phonics (p. 15), and capitalization (p. 2) to be most interesting.