Here's the snopes entry - in case your computer is slow.
Note that it does not say the sign up is a scam but rather the post card tht came in the mail is the fraud.
The sign up is legal and - according to national newscast last night - several million have already signed up, nationwide.
This is to all of you that signed up for the "do not call" law. This week I received a card in the mail that looked alright — It said "vote for your favorite cola — Pepsi or Coke — and receive a complementary 12 pack" It didn't look suspicious — but for some reason I kept looking at it.

THEN I FOUND IT !! At the bottom of the card there is a VERY small statement. It is SO small it is hard to read—but here is what it says— By completing this form, you agree that sponsors and co-sponsors of this offer may telephone you, even if your number is found on a do not call registry or list"

This REALLY upset me and I just wanted all my friends to be aware of this way to get around the "do not call" law !! Just think how many people will send this in and their do not call registry will be NO GOOD !! The company's name is MARKET SOLUTION. Please send this to all your friends that signed up for "do not call". I think this is just one of what we will get in the future—so READ EVERYTHING before you SIGN AND SEND !! AND TELL YOUR FRIENDS ABOUT IT.!!!! PLEASE !!!