FEATURE: Loyalty Rewards Program

Foster customer loyalty and generate repeat customers using a built in  Rewards program for orders placed on your store(s)!

Currently this is supported in 2013.1 version sites and once turned on and configured works for all purchases on the store.

Customers can earn points on purchases, registration, leaving reviews, social sharing and more!
They can also use these earned points as a payment method upon checkout.

For more details see the knowledge base article here