Why not? 2 months is just more than enough !! Yup, I know some 2-3 forum admins myself, and they did bring good amount of traffic to their site within a few days like 20-30 days !! I don't know what they did.
I think NB is not looking to spam like them That's a good thing though !! I joined NB without anyone telling me - it was from DP - I think so.. from someone's signature spot !! I think its from Will's or MG's sig.