According to the tipster, the studio is aware of people's feelings regarding the look of the Turtles as well as a white Shredder.
The tipster says he got the image early as the studio wants to "soothe folks' nerves."
I haven't been able to find the image online, and I also inquired about it at the TeenageMutantNinjaTurtles.com fansite who haven't seen it, but mentioned the look of the helmet may be different.
If someone has seen it previously, feel free to comment below and we'll make a correction.
Update: More than likely a fake as Paramount would have requested we take this down. And as the comments mention, it looks a lot like 47 Ronin.
"Teenage Mutant Ninja Turtles" has an August 8, 2014 release directed by Jonathan Liebesman, produced by Michael Bay starring Megan Fox as April O'Neil, William Fichtner as Shredder, Pete Ploszek as Leonardo, Alan Ritchson as Raphael, Jeremy Howard as Donatello, Noel Fisher as Michelangelo, Will Arnett as Vernon Fenwick, and Whoopi Goldberg as Bernadette Thompson.
The city needs heroes. Darkness has settled over New York City as Shredder and his evil Foot Clan have an iron grip on everything from the police to the politicians. The future is grim until four unlikely outcast brothers rise from the sewers and discover their destiny as Teenage Mutant Ninja Turtles. The Turtles must work with fearless reporter April and her wise-cracking cameraman Vern Fenwick to save the city and unravel Shredder’s diabolical plan.