Following in the steps of Amazon and Wal-Mart, Google has launched same day delivery, just for certain San Francisco dwellers for now, reports The New York Times's Clair Cain Miller. You may be thinking, wait, Google doesn't sell things or have warehouses or stores. But, unlike Amazon or Wal-Mart it plans on teaming up with retailers and shipping companies, says Miller. Earlier this month, the U.S. Postal Service filed a notice about trialing its own S.F. initiative to offer same day delivery. It plans on partnering with 10 online stores at first. Maybe Google is one of them? Cain mentions a vague "several San Francisco retailers, including national chains" who are participating in the prorgram already. For now only "some people affiliated with Google" have access to the set-up. And Cain doesn't offer further details on how much it costs, or how it works. But, since the company has to work with so many parties, we imagine it will take more time for them to get things organized.