* Kathy Sierra is adamant about the idea that you never pay your evangelists. I hold her advice in high regard and I can understand her arguments: http://headrush.typepad.com/creating_passionate_users/2007/02/inspiring_your_.html
* in any cash-back incentive program you introduce the ability for people to game the system. I suppose it requires willingness to accept some level of that in trade for the boost in visibility.
* energy devoted to implementing the program is potentially be better spent on other evangelism activities (Joel Spolsky in Founders at Work said none of the sales-generating gimmicks he's ever tried has had more ROI than investing time in improving the product - http://www.grid7.com/archives/143_faw-25-joel-spolsky-of-fog-creek-software.html
But at the end of the day, I'm really curious if the referral program could substantially boost our word of mouth. This forum always has insightful startup advice - I'm hoping to get input (good or bad) from folks who have conducted referral programs or other successful activities to get the awareness ball rolling.
sean