http://www.eurogamer.net/articles/2015-12-11-overwatch-interview
We feel like ranked play is extremely important for the game, in fact we had a really deep, meaningful meeting amongst the design group about it yesterday. We're pushing super hard to get it into the launch of the game. If we don't feel good about the direction in which it's going or that it's not a Blizzard-worthy feature, we'd rather it slip the launch and come in sometime shortly after. We're not far enough along yet to know whether it's going to make that window or not, but I do feel confident in saying that if it doesn't make launch, it wouldn't be long after.
Discord