Amazon may be looking to launch a same-day delivery service, which could have a serious impact on U.S. booksellers.

Retailers breathed a sigh of relief after Amazon agreed to charge sales tax on their products in eight new states, starting this fall with California and Pennsylvania. But Amazon’s decision to stop fighting state tax laws may signal a change in the company’s strategy.

The online retailer currently ships orders from a few large warehouses located in low-cost states. Now that Amazon will be charging sales tax, it can legally set up smaller distribution centres closer to more populous urban areas in states such as New Jersey, Texas, and Virginia. Two new distribution centres planned for California will service the Los Angeles and San Francisco areas, dramatically cutting down delivery times.

In an article for Slate, Farhad Manjoo writes about why this should be a concern for bricks-and-mortar retailers:

Amazon’s new goal is to get stuff to you immediately ” as soon as a few hours after you hit “buy”¦ Same-day delivery has long been the holy grail of Internet retailers, something that dozens of startups have tried and failed to accomplish … If it can pull that off, the company will permanently alter how we shop. To put it more bluntly: Physical retailers will be hosed.

Manjoo says Amazon is investing billions of dollars to make its deliveries more efficient, with new efforts such as collection lockers in local drug stores.

Amazon has not officially confirmed it is looking at same-day delivery, but in the meantime, Appnewser has posted this parody video: