Your status will change automatically as you stick around and post. The explanation (though I'm not sure how old it is) goes like this (though it has been "tweaked" a little here and there):
1 - Trial Membership
Upon joining CAF you are automatically given this title. It just means that you are checking out the forums, taking it for a spin, so to speak. This group does not have signature and graphics posting rights.
2 - New Member
After making some posts AND accumulating a couple weeks of membership*, "trial" members graduate to this title. New Members have some limited signature and graphics posting rights.
* Yes, I'm being purposefully vague. Some additional tweaking may occur to the "promotion" rules.
3 - Junior Member
After 100 posts AND 90 days members are given this title.
4 - Regular Member
After 500 posts AND 6 months members are given this title.
We anticipate that most of the forum membership will reside in this group.
5 - Senior Member
After 6,000 posts AND 2 years members are given this title.
6 - Veteran Member
After 9,000 posts AND 3 years members are given this title.
7 - Forum Master
After 12,000 posts AND 4 years members are given this title.
8 - Forum Elder
After 15,000 posts AND 5 years members are given this title.
Hope this helps!