I tend to shy away from US-only news as it is so amply covered elsewhere, but for the benefit of readers outside the US who may have missed this big story but will be eager to get a share of the action, I copy below the official statements from both Kobo and Walmart stating their respective positions.
For authors and publishers access to the Walmart ebook store will be automatic is you are listed won Kobo either directly or through an aggregator.

From Michael Tamblyn at Kobo:

Walmart’s New Digital Book Offering is Worth Exploring

As an avid book lover, I couldn’t be more excited about the new digital book options now available through Walmart eBooks by Rakuten Kobo. As we begin this new partnership, I wanted to share a little about who we are.

Rakuten Kobo was created in 2009 to empower booklovers to read more by delivering the best digital reading experience possible. We began internationally where we built everything – infrastructure, apps, payment processing, e-commerce stack – knowing we would be operating in multiple countries, in multiple currencies and in multiple languages. This enabled us to quickly expand all over the world.  Today, we deliver content in 190 countries and have localized online stores in 24 of those countries.

Although we are a company that focuses on selling a digital product, retailers and store experiences have always been an important part of the mix in every country we operate in. That’s why we’re excited to partner with Walmart as we grow in the U.S. market. Together, we can provide even more people with a great reading experience, whether that’s print, digital or both.

I say both because we know that digital vs. print isn’t “either or.” Today, about one in four books sold in the U.S. is an eBook and in some categories like romance, mystery or fantasy, it’s more like one in two or three. Our best eBook customers tell us they also buy a dozen or more print books a year, as well as digital audiobooks.

We are a company devoted to reading, and we’re looking forward to getting to know Walmart customers who already turn to Walmart for great books at great prices. With our catalog of more than six million books, we know you’ll always find something great to read.

 

From Mario Pacini, General Manager, Entertainment, Walmart eCommerce U.S.:

Walmart and Kobo Launch Walmart eBooks, Including an Audiobook Subscription for $9.99.Walmart and Kobo Launch Walmart eBooks, Including an Audiobook Subscription for $9.99.

 

Summer is almost over, which means there are only a few more weeks left to soak up the sun and enjoy one of the beach reads all of your friends have been talking about.

Today, we’re making it easier than ever to check out the latest new releases with the launch of Walmart eBooks by Rakuten Kobo, Walmart’s partnership with Kobo to offer an all-new digital books catalog in stores and online.Walmart eBooks will complement our vast physical book assortment and offer customers a comprehensive digital book solution, introducing an entirely new category that hasn’t been previously available at Walmart.

Walmart eBooks brings customers:• Kobo’s library of more than six million titles – from New York Times best sellers to a wide variety of indie titles and children’s books.

• A new monthly audiobook subscription – Customers will be able to subscribe to our audiobook service for $9.99 per month, which includes one audiobook per month.

• The ability to purchase digital book cards in 3,500 Walmart stores – We’ll offer nearly 40 titles including The Power of Now by Eckhart Tolle, Astrophysics for People in a Hurry by Neil deGrasse-Tyson and Capital Gaines by Chip Gaines. These cards will roll out to stores beginning this week.

• Access to Kobo’s eReaders online and in-store –Starting today, customers can choose from a variety of Kobo eReaders on Walmart.com. In 1,000 stores, we will offer the Kobo Aura starting later this week.Walmart eBooks will be accessible through co-branded iOS and Android apps, which also launched today, and on Kobo eReaders.We’re really excited about this new category, and we know our customers will be too.

To celebrate the launch, we’re offering first-time customers who sign up online $10 off their first a la carte eBook or audiobook. In addition, customers who sign up for the audiobook subscription will receive a 30-day free trial.

We’ve been hard at work expanding our assortment on Walmart.com overall – from dramatically growing our product assortment in the baby category and announcing a new fashion partnership with Ellen DeGeneres, to introducing entirely new categories like the one we’re unveiling today.

So, as you’re gathering all the essentials for the last long weekend of summer, don’t forget to shop for an eBook or two.