Blizzard is never really the fastest on anything, but now at least Cross-play has finally come to Overwatch between all platforms.
Blizzard confirmed a few weeks ago that they are working on support for cross-play in Overwatch and now it finally seems time.
In the latest update, it is now possible for players on PC, Playstation, Xbox and Nintendo Switch to play and meet each other. However, this does not apply in Competitive where all platforms can play for themselves.
To get started with cross-play between the different platforms, you must have a Battle.net account.