Well, there are many things to consider.
Do your galleries suck?
Does your sponsor suck?
Do you suck? - just kidding.
Seriously, sometimes you can get 3,4, maybe up to 500 with no signups, then all of a sudden you'll get 3 signups. It takes time to figure out why. Was is it a text link? Was it a certain girl? Was it a banner? All of that you will just figure out in time.
There is one sponsor (that I know of) that will display there ratios online for the webmasters to see, SoulCash. Right now they are converting 1:210 with BraveGirls, so maybe you don't need to ditch a sponsor so soon, but trying another sponsor in the meantime is a must.
You should always have 2 or 3 different sponsors.
Check my signature below to see more sponsors.
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<A HREF="http://www.soulcash.com/content.htm?sc9redshoe" TARGET=_blank>
13,000 free pics and videos
Join SoulCash Now!
BraveGirls.com is converting 1:210</A>
<A HREF="http://www.usexfan.com/webmasters/moneymaker/" TARGET=_blank>
</A>
BoneProne Family Member