Microsoft officially took the wraps off of Windows Phone 8.1 today at its Build Developer Conference, and now that the update has been confirmed, carriers are starting to come forward with their WP8.1 rollout plans.

Sprint has confirmed that it plans to update both its HTC 8XT and Samsung ATIV S Neo to Windows Phone 8.1 this summer. Meanwhile, T-Mobile says that its Lumia 521 and Lumia 925 will receive the Windows Phone 8.1 update this summer, as will the MetroPCS flavor of the Lumia 521.

Windows Phone 8.1 is a major update to Microsoft's mobile platform, bringing with it a legit notification center, Cortana personal assistant, Start screen background images and a number of other big and small features. Perhaps one of the best parts of the update is that it's hitting all Windows Phone 8 devices, including the high-end Lumia 925 down to the entry-level Lumia 521, meaning that WP8 users won't have to worry about missing out on the update to 8.1 because of the device that they've got.

Via @SprintNews, T-Mobile