This comes via Ninja Turtles producer Galen Walker, who posted the following on Facebook (the post subsequently appears to have disappeared):
"Ok- Cool Beans folks! the new “Ninja Turtles” Teaser will make it’s debut in front of the New Captain America Film- April 4th. We are ready and prepared for lift off! Been a long haul."
"[Teenage Mutant Ninja Turtles] always had sort of a bouncy cartoon feel to me, which is great, that's why it was appealing. That's not this movie... It's not like any Mutant NInja Turtles thing you've ever seen before. It's freaky, they're cool, and they're mutants, and they look awesome. It's tough, and it's going to be really, really great."
Ninja Turtles hits theaters on August 8, 2014.