Warner Bros, which is financing along with Legendary Pictures, just announced the date.  For now, the film has the prime summer real estate all to itself, and since it's more than two years away, studios will be scheduling their big summer releases around that mid-July date.

Talking to Collider before the announcement yesterday, del Toro himself shared an update on the project's development, saying,

Fantastic. I mean so far, knock on wood, it’s the greatest experience of my life. I’m having a blast, designing like crazy. I’m now hiring actors, which is always a good sign, always a great sign when you’re casting. We’re announcing a release date today or tomorrow, which makes it real also. The other thing that we’re heading towards is an impeding start date the first week in November, so we have 20 weeks to start shooting the biggest giant monster movie ever made.

While his declaration that Pacific Rim will be "the biggest monster movie ever made" obviously draws the attention, particularly from a director with del Toro's history creating monsters, you might also note a sense of skepticism amidst the gleeful hyperbole.  That is likely because the director just spent months each developing The Hobbit and his dream project At the Mountains of Madness, only to see the former languish in development due to financial woes and the latter fail to get a green light.

So the man behind Pan's Labyrinth and Cronos will be back with Pacific Rim in July of 2013.  The screenplay was written by Travis Beacham, who contributed to last year's Clash of the Titans.  Idris Elba is currently in talks to star in the film alongside the already-cast Charlie Hunnam, both of whom will play pilots of the aforementioned giant mech-bots.  It's Always Sunny in Philadelphia's Charlie Day is also a likely addition as a professor who probably has some inside information on the alien beasties threatening all mankind in the near future.