This question has come up enough times to merit its own post. The following are the amount of posts needed to achieve a new 'ranking:'

0-99 Newbie
100-199 Hocker
200-299 Masmid
300-399 Shtark
400-999 Gabbai
1000-2499 Rebbe
2500 Godol Hador

Anything above 3000 stays at Godol Hador, but at this point, you also have the option of making your own custom title. Additionally, if you have a blog and link it to this website, you can PM Silent J with your URL and request for a custom title.