Ranks on AP Minecraft as of December 2011 are as follows:
Guest – Rank all new users receive. Are muted.
Member – Regular users, can build and explore.
Builder – Users with a worthy build, can further enhance their build experience.
XBuilder – Users with 2+ worthy structures. Are contributing members.
ProBuilder – Unbelievable structures and buildings. Out of the ordinary.
HeadBuilder – Very, very good builders, help out others and have good builder experience.
Engineer
VIP
Lord
King
Trainee
Moderator
EliteMod
Diplomat
MCBans
Admin
Owner