From Inside Google, two stats about Google Checkout:
* Amount Google spent to promote Checkout in '06: $58mil
* Amount Google will earn in Checkout fees in '07: $0
If you hadn't heard, Google is processing transactions for free for all of 2007.
(I'm half expecting the hardware wizards over at Make to hack a credit card scanner to allow small brick-and-mortar retailers to clear transactions this way.)
Nathan Weinberg observes: "Google is pushing Checkout by buying its way into the market."