How often you get a survey in planet-pulse?

I am a 3-week old member. So far, I have not received any surveys yet. I think you receive pulses here which are like points that can be converted into cash. You can receive pulses once you answer surveys or earn referrals. A lot of survey sites promise us that we'll be receiving surveys thru email after updating our profiles and interests. I always do this but none of them had every come to my mail. Are they considered as scams also? I think I can equate planet-pulse with surveysavvy. I actually signed up for these two sites on the same day but never received mails from them. The last emails I have on my inbox are the activation/registration messages.

It depends. recently there is no any survey for me. but last year I have quite many surveys. I got paid 78 dollars (3times) in last year. It is one of my favorite.