I am in the affiliate scheme, but I find the amazon one is better. In terms of book sales Smashwords can be erratic - I've some books that are doing exceptionally well and others that have barely moved even when free.
Excuse my ignorance. But what are these affiliate programs? What is the purpose and who should/can join them! Thanks for sharing, Jeff. Glad someone responded.
Affiliate schemes are schemes where you get paid a small percentage every time someone buys the book from your website or through the affiliate link. With Amazon, the tracking lasts longer and if the user who clicked on your link buys something other than the book, you get credit for that sale. Details of the Amazon.com one are
here.