Your best cheerleaders don't want/won't accept won't redeem the referral certs., for most a thank you card will suffice. i do however understand that's easy for someone who's been in business a while, and has a solid customer base, BUT that doesn't make it any the less true.
Also remember once you start something like that, it can be difficult to end it, as some clients (a select few) will be accustomed to it and may get antsy if you stop it, i think.
Have any of you guys ever stopped or changed your referral program, and how was it accepted? I started the "10%" referral thing back in 98, worked ok, but hardly worth it now, more paperwork than anything else.