This is really bugging me because I can't confirm it right now.
A few hours ago when me and Captainthorrawr finished putting the guild at lvl2, it was still showing10/10 however that link that you posted says that they changed it so now it would be 10/20.
Once I get back from work I will try to invite someone to the guild and see if we can really have more than 10members at level 2.
We made the guild like 2 or 3 days ago and it's already full and we are in Hieron! Level 3 here we go!
Eat that you union of onions!! XD