This issue was
raised again recently.
There's no doubt that
falafel is the more commonly used spelling throughout the English-speaking world - by a factor of 10 or thereabouts.
As it happens, the place where the
felafel spelling is used most often is here in Australia, which might explain how the words came to be classified the way they are. Perhaps the Australian use of this variant is influenced by its use in the title of John Birmingham's 1994 novel about share house life,
He Died with a Felafel in his Hand, and the subsequent film of the same name. But even in Australia the
falafel spelling is in a clear majority.
So
felafel should certainly be treated as rare in future. But should
falafel become common? The word probably isn't used quite as often as the names of some other popular snack foods -
kebab,
taco,
sushi - but I think it's well enough known to warrant common status. So that's what it will be from now on.