A host of new features were included in Windows 10 build 17074 which was released by Microsoft to the Fast ring a couple of days ago. However, it seems that the official changelog did not list the fact that the Microsoft Messaging app was being revamped with Fluent Design as well.
As can be observed, the messaging application now includes Acrylic and Reveal effects. Interestingly, this is the first major update for Microsoft Messaging since 2016. Perhaps, the long rumored Andromeda device (also referred to as the Surface Phone) is the underlying reason behind the step undertaken by the tech giant, as this device will supposedly enable users to call and text as well. This is where the updated Microsoft Messaging app comes into play.
However, it should be kept in mind that this application cannot be used to actually send text messages on PCs. As such, the Andromeda device's involvement with Microsoft Messaging will presumably call for a more functional application, rather than simply an aesthetically pleasing one.
As many of you will know, the effects added to this app are part of the Fluent Design System, which was first announced by Microsoft back in May, 2017. Initial implementations of this system were observed with the release of the Fall Creators Update, around three months ago. More of this design is expected to be showcased with Redstone 4, Microsoft's upcoming feature update.
As of yet, there is no indication that these changes will be rolled out to Windows 10 Mobile as well. Nevertheless, this is quite possibly a refreshing change for plenty of Windows 10 users, and it proves to be yet another another addition to the growing implementations of the Fluent Design System.