First of all, some guy's "guesstimate" is basically meaningless. And the "10% of world modelers" figure... where did he pull that from? I think we all know... where the sun don't shine.
Second, this is 2011, not 1998-99.
To quote myself, there's no way to know.
If anyone can come up with a reasonable, logical, accurate and indisputable way to count how many modelers there are, please post it here. I guarantee you, you'll be the first.