It turns out that Samsung is pre-loading the Galaxy S21 with Google Messages in most markets, as Engadget learned from an interview with Google's Hiroshi Lockheimer yesterday. By doing so, Samsung joins other OEMs like OnePlus, LG, and Motorola in using Google's messaging app by default. Unfortunately, we in the US are stuck with the regular Samsung Messages.
With all of the rumors and leaks we've heard about the Galaxy S21 family, there's little left to the imagination at this point. That said, if you wanted to see what Samsung thinks are the most highlight-worthy features of its new flagships, you're in luck; Roland Quandt of WinFuture has posted a few of Samsung's marketing images for your perusal.