Go back to the old way of sending birthday cards. This method of stopping people until the upgrade dissuades non-members fromsigning on to send cards and thereby greatly lessens the traffic to the sight and will cause it to wither eventually. I know you have to monetize, but you are doing the opposite. Offer something of value rather than taking something away something that draws people to your site.
I don;t know if you've eer done this, but why don't you make real gifts available from Geni, such as home delivered flowers, fruits, balloons, candies, etc. I imagine that there are enough vendors out there who would love to make a deal with you.
