It's a browser plugin, right? Click install, money trickles into the charity. I would probably use this if the plugin runs on my OS of choice. Why not give a bit of free money to charity?
By the way, shopwisely.org gives 100% of commissions, and is a bookmarklet which works in ie, firefox, chrome, and safari.
But once you get the users on your side you'll have to get the merchants on your side by convincing them it will help business. Also the affiliate communities frown on "stealing" tracking cookies. They hate what UPromise does, even though I've argued it's not wrong at all.
I stopped doing it because I stopped believing in the "world changingness" of the whole idea. a) nonprofits don't like to raise money for the sake of raising money, and it usually took months before the money could be sent out. So they couldn't plan how to use the money raised. b)the idea isn't really better than direct donation except we're introducing a new middleman, and making it less transparent because the merchant now pays charities with money they get from the end consumer.
> Why not give a bit of free money to charity?
I want to mention that it's not really free money. In the end the consumer pays because the merchant pays.