Soooo... you're saying it's inappropriate to call them "Limeys," so we should call them "Jaffas"?
At the very least "Limey" has a great deal of historical value (like Yankee)... I mean, I dunno -- I guess I'd like all the Brits out there to give their input: which would you prefer, "Limey" or "Jaffa?" I don't expect anyone will stop calling us "Yankees" anytime soon (nor would I want or expect them to), but it seems reasonable to at least inquire as to what (semi derogatory) term they'd prefer to be called!
As a Yank with a number of Limey friends, I'm rather fond of calling them all "Limey Bastards"; it rolls off the tongue, much as "Yankee Barbarian" or "Yankee Swine" (as they are fond of calling me, I can't imagine why...)
Hehehehe.

Rock the hell on, y'all, Yankee and Limey alike.

--Jaeger