Echo, the 32nd Overwatch hero, is available on the PTR. Among our IGN colleagues, Jeff Kaplan has expressed his opinion about the new DPS, her in-game abilities, but also the fact that she will be the last hero to be released on the original Overwatch game.
Jeff Kaplan is Blizzard Entertainment Vice President, but also and most importantly — for what we're most interested in — Overwatch Game Director. He's the one you heard in the last Developer Update, and all the previous ones, and he's one of the most active people in communicating about the game.
For example, he took part in a stream with TimTheTatman before the official release of Echo on the PTR:
Echo was in development for a long time, and she was part of the game long before its release. She was part of the Titan Project — which was cancelled before it finally became Overwatch as we know it today. Her history has been written for a long time, and her role in the game's universe is very important.