After weeks of quiet preparation, Amazon this morning officially launched its Prime Now one-hour delivery service in the Seattle area, operating through two new distribution hubs, in downtown Seattle and Kirkland, Wash.

The launch also marks the U.S. debut of beer, wine and liquor delivery through Prime Now in the United States. Customers can select from a range of beer and wine for one- or two-hour delivery, along with whiskey, vodka, rum and other hard liquor.

The official announcement follows a series of reports by GeekWire about the company’s plans to launch Prime Now in its hometown. The location near Amazon headquarters gives the company a chance to experiment with new features of the Prime Now service.

Seattle becomes the 10th Prime Now city, and the first on the West Coast, following the original launch in Manhattan in December.

“Prime Now is our fastest delivery option ever. With Prime Now, you can skip a trip to the store and get the items you need delivered right to your door in under an hour,” said Stephenie Landry, director of Amazon’s Prime Now service in a news release. “Customers love the convenience of one-hour delivery and we’re excited to bring Prime Now to our hometown customers in Seattle and surrounding areas.”

However, Amazon’s news release did not acknowledge or reveal any official details about Amazon Flex, the new package pickup service that we spotted at the Prime Now distribution hub in Kirkland last week. “We have a longstanding practice of not commenting on rumors and speculation,” an Amazon spokesperson said in response to our inquiry this morning.

Prime Now operates between 8 a.m. and midnight, seven days a week, accessible through the Prime Now app. It’s available only to members of Amazon’s $99/year Prime Now membership program. A minimum order of $20 is required. One-hour delivery costs $7.99 and two-hour delivery is free.

We’ve already made our first small order of groceries through Prime Now, for delivery to Ballard between 8 a.m. and 10 a.m. As would be expected, the selection of groceries is more limited than with the AmazonFresh grocery delivery service. For example, through Prime Now, we were only able to purchase half-gallon containers of milk, not full gallons.

However, on the items that are available, the prices so far seem to match those offered through AmazonFresh.

Update: Our Prime Now delivery arrived around 8:40 a.m., delivered by a driver named Bob, whose progress I was able to watch on a map in the Prime Now as he approached our house. Everything went smoothly — even the eggs were intact — although I did miss an opportunity to test the alcohol delivery. We’ll try that later today.