KillerStartups describes it as follows:
a service whereby testimonials and referrals are socialized by the use of elements such as profiles and pictures that let everybody know exactly who is who. And the Twitter influence is felt in the way that testimonials are provided - they are streamed on your the in a manner not that dissimilar to how tweets are displayed on the public timeline of Twitter.
The way the system works involves creating links to prompt people to prop you. These are placed not only on your site or blog but also on e-mails, and the resulting feedback will be automatically collated for you to weigh up.
In addition to being employed to generate higher sales, a system such as this one lends itself to complementing colleagues and giving recognition to city workers by recognizing what they have done for you.
This system is free both for companies and individuals. All that is required is creating an account beforehand, and that is done in less than 30 seconds.
Read more: http://www.killerstartups.com/Web-App-Tools/propadoo-com-centralizing-referrals-testimonials#ixzz0ebNZpPSh
From Propadoo's own web site:
Individuals are using Propadoo by:
Make their compliments count by using Propadoo to preserve and promote them
Complimenting colleagues for a job well done
Recognizing teachers, coaches, civil servants etc. for going above and beyond expectations
Using positive reinforcement by telling someone what they’re doing right
There are some interesting posibilities here. I like the idea even if they haven't done exactly what I would have done with it...

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