It doesn't make much sense to have people in Essos think so little of Westeros when it's nearly the same size - particularly when much of Essos seems to be so thinly populated, what with the enormous Dothraki Sea and equally enormous Red Waste taking up nearly all of it.

But let's see what the book makes of it, I guess, hopefully they'll do a better job... and a more original one, I might add, to the extent that's still possible. Someday someone (okay, other than Erikson) is going to make a fantasy world that is not just a rip-off of Earth. And perhaps even have the East be the good guys for a change...