Ten is "decem" in Latin. Decimal means, literally, base ten. It's a tautology either way. You can't even specify the base of the base since "base (10 in base 10)" presents the same problem recursively.
It's a non-problem though. I don't know about mathematicians, but when programmers say base N they mean N in decimal.
"10" is never correctly called "ten" except in decimal. But this whole tangent is getting a little navel-gazey for me. "Base 10" is fine in my book because decimal is our inbuilt base.
