nomis5 - 5:50 am on Aug 27, 2013 (gmt 0)
Here's my opinion but it's no more than that.
G seems to concentrate on the main site as far as the SERPS are concerned, they really don't have a SERPS for mobiles. There are a few grey areas though, the SERPS do seem to differ when they relate to a geographic term.
There is a big "but" though. Even though there really isn't any different SERPS for mobiles at the moment who's to say that might not change tomorrow. So I would design your mobile version of the site as a stand alone entity which can stand up in the SERPS all by itself. More future-proof.