If you are a participant in Project 94, you should have gotten a feedback form in your email. I was a member of Project 90, myself. (Though, unfortunately I was not able to complete it because I couldn't get enough friends interested in Akatoo.)
On my feedback form, I was asked to report how many of my refered people:
~ Had gone to the help section to better understand IKU.
~ Understood the process of questions closing.
~ Understood both promotions.
~ Subscribed to a category.
~ Gained positive IKU scores.
~ Would continue using IKU scores.
I was also encouraged to include additional information, such as comment and suggestions from the people I refered.
As I said, I never completed project 90 (though I think I might still be able to), but the form says to confirm my address so they can mail the check. So, I would assume that you do, in fact, get the check in the mail.