Oprah Winfrey recently let everyone know just how much she loves Microsoft's new Surface tablet, by tweeting about it via her iPad.

“Gotta love that SURFACE! Have bought 12 already for Christmas gift,” Oprah tweeted Sunday.

The tweet, however, explicitly shows that the endorsement was published through the Twitter for iPad app.

TechCrunch notes that Microsoft has spent $1.5 billion on advertisement for its latest operating system, Windows 8 and Windows Phone 8.

Several celebrities including Jessica Alba and Gwen Stefani, among others have endorsed Microsoft’s new software and products.

Winfrey even selected the Surface tablet was one of her “favorite things” for the list in her Magazine, “O,” as well as the TV special that also aired Sunday.

But her slip may suggest an unspoken preference for Apple products. In 2010, the newly released first generation iPad was Oprah’s “favorite thing ever.”

According to TechCrunch, Oprah’s gaffe illustrates an ongoing criticism of Microsoft’s delay in releasing an official Twitter client to the Windows Store.

While Windows users can access Twitter via third party clients such as Rowi and MetroTwit, the lack of a direct connection to the social media platform reportedly suggests that developers may not be putting as much energy into creating apps for the Windows Store.

Microsoft has experienced a numerous unfortunate incidents as of late.

The Surface tablet released in October to mostly negative reviews, including critiques of a lack of apps.

Weeks later, head of the Windows division, Steve Sinofsky resigned.

Oprah’s tweet culminates a rough few months for the corporation.

 When contacted about Oprah’s tweet, Microsoft was unavailable for comment.