The title of howto/cporting.rst is "Porting Extension Modules To 3.0".  It then talks about 3.0 in a whole bunch of places.  Considering that we're working on 3.3, and considering that 3.0 is end-of-lifed (not even meriting a branch in hg), wouldn't it be better for the document to talk about "3.x"?  It already talks about "2.x" in several places, so it's not like this would confuse the reader.

Alternatively, we could remove the ".0" (and maybe the ".x"s) so the document talks about porting from "Python 2" to "Python 3".

I'd be happy to make the patch / check in the change.