Sombra is out on the PTR right now. Haven't got a chance to play her but she seems tight.
Plus, they put on "the Arcade". This includes new 1v1 and 3v3 ELIMINATION game modes on a new map, a random brawl, the "mystery hero brawl" (the most popular, and fun one imo) and a no-hero limit quick play (hero limits are being implemented in quick play).
Tons of stuff to check out on PTR right now so if you're an Overwatch player, hop on in!