Erik Moeller wrote:
When dealing with the name of a people, it is proper to go by popularity alone. When dealing with a language (or, like Occam's Razor, a philosophical concept), the opinions of scholars must weigh more than the Google count alone.
I would add that these "rules" _tend to be true_ (maybe), but that it does depend on the particular case. I would say that when dealing with the name of a people, popularity is a strong factor, but also what they call *themselves* is a strong factor. How hard it is to spell, how likely the "correct" term is to become popular in the near future, etc., all of these can be taken into consideration.
--Jimbo