Class B Address

Dear all, Can someone point me to some documents/weblink on how many class B addresses are still available? Have the registries like RIPE/ARIN/APRIN exhausted class B addresses already? IPv6 Forum presentations have me believed class B addresses are exhausted and the situation is especially bad for country like China. However, after checking with some Chinese I was told just the opposite. So I am wondering is address scarcity just a hype? Appreciate any information you guys can share. Cheers, Hansen