yeah, there's dozens of terms for this kind of mixture-english.
i used to write a paper about something in linguistics and one of the ressource books was labelling it "euro-english" as the kind of english used by non-natives to communicate with other non-natives.
"englishes" is another term used for this
rules and style are mostly neglected in favor of "understanding" and ease of use. the term they used in that context was, if i remember correctly, "intellegibility" (i remember this cuz' it's a bit difficult to say for me)
i gotta admit that's what i write in those forums and emails and if i say that it works efficiently with people from many places, then this is a very cool thing.
on the other hand, i share poper's approach on AE: it doesn't sound so nice all the time. It's like the northern german idiom where you get the feeling that people try to talk without opening their teeth
there's two points of view: descriptivists and prescriptivists.
for the latter, what i'm writing here isn't english, it's just some substandard bastardisation of the great english language (you could almost hear sidney nettleson talking)
for the former, they say that any existing language and languages exist as such and that, as popers states, change has always been part of the languge. of course, this change can be much faster in london than maybe in the outback because of the demographic.
but i think linguists were (and maybe are still) debating about this topic, depending on the point of view, with more vigour (does that have an "ou"?) or less.
