According to D.Va's lore she is a competitive Starcraft player with quite a few victories to her name, so it shouldn't come as much of a surprise to hear that she will be making her way into Starcraft 2. What might come as a surprise, however, is that she will be arriving as one of the seven announcers releasing with Patch 3.7!
So if you feel like your Starcraft 2 experience can only be improved by having a teenage Korean girl shout at you, then head over to the Blizzard website and check out what D.Va has to say. My favorite line so far is the Zerg #2 one: "You have a new Queen, shooooow me those skills!"
And now for some bad news - the only way to get D.Va is to purchase the BlizzCon Virtual Ticket (or the real deal, but I'm pretty sure that ship has sailed by now). In other words, unless you're willing to pony up $40 I'm afraid you won't be able to listen to "WINKY FACE" over and over again. Whether the ticket is worth the asking price, that I'll leave for you to decide, but I wouldn't recommend purchasing it for the digital goodies alone.
Finally, if you would like to learn more about the other announcers and what sort of cosmetic items are coming with Patch 3.7, here's a video overview Blizzard released a little while ago: