Mark, On the one hand I favour the idea of a seperate mailing list about languages and all the huha that goes with it. It would mean that some people could talk to each other endlessly. FINE.
However, however much is discussed there, what does it amount to except for things having been discussed on this list. What do you expect that a "consensus" reached on this list means outside of this list ?? The wikipedia-l is about issues that transcend the concerns of any particular wikipedia project and therefore things NOT discussed on this mailinglist and/or on META do not have enough exposure to amount to something that signify a relevant and adequate consensus.
So, have this list if you must but do consider its worth.
Thanks, GerardM