Light Blue-Super Mod-Invite only
Blue- Moderator-Invite only
Light Purple / which is sort of a bluish green badge-SF Team-Invite only
Purple- Seven Pro
Sort of Fuchsia color-Power User
The colors are just different ways of telling the status of members.
It takes a certain amount of rep and posts to reach a certain level.
And the Admins can promote whomever they see deserves it.
This link below is from the Vistax64 site, but it shows the points a member would have to reach to get a certain level, unless they're promoted by the admins first.
Forum Rules - Vista Forums