Google announced today in the official AdSense blog that they are now offering referral money to AdSense members who successfully convert visitors into Google Checkout members. Google has been offering similar monetary incentives previously for AdSense, AdWords, Firefox with Google Toolbar, and Google Pack.

From the AdSense blog, here are the specifics on how it works and how much you can earn:

1. You place the Checkout referral button on your site.
2. Someone clicks on the button, signs up as a buyer with Google Checkout using a valid U.S. credit card, and completes a purchase of at least $10 before shipping and tax through Checkout within 90 days. (The current $10 minimum purchase corresponds to our existing $10 promotion for new buyers, so this amount may change in the future.)
3. You earn $1.

The detail involving the new buyer spending $10 within 90 days of joining is standard when compared to Google’s other program offers. For example, AdWords requires a certain cash amount to be spent within a certain period of joining, while AdWords requires a certain earnings figure within a specified period of time after joining. Firefox with the Google Toolbar must be installed and used after downloading before referral cash can be earned.