A reliable source confirms rumors of Google Wallet. As Wired Magazine put it, this payment system would sidestep click fraud, the major threat to Google's revenue.
Basically, when a customer clicks on a Google ad, Google could handle any payments they make at the advertiser's site. Google takes a cut of the purchase instead of money for the first click-through. Bang, no more click fraud.
Gotta hand it to them — if Google rolls the Wallet out in time, they could save their revenue stream, and Larry won't have to go crazy over his falling net worth.
Background: How Click Fraud Could Swallow the Internet [Wired, page 3]