https://www.gamespot.com/articles/huge-overwatch-update-now-live-with-new-map-and-me/1100-6453447/

As a new piece of content, the headlining feature of today's Overwatch update may be the Junkertown map, but more meaningful are the balance changes the patch makes. Among other things, these include the overhauls for both D.Va and Mercy, both of whom now play much differently.