Disregard that useless “sticky” posting. The current API docs are here: http://www.blender.org/documentation/blender_python_api_2_64_9/
I’m not sure if the BMesh explanation is sufficiently detailed yet; it may be helpful to refer to the design rationale here: http://wiki.blender.org/index.php/Dev:2.6/Source/Modeling/BMesh/Design
Well, the sticky posting says:
and it redirects to the URL you posted... So what's wrong with it?
I'm sitting, waiting, wishing, building Blender in superstition...