I would guess that their research only shows that light can be bent around a simple object like a disk or sphere, and not an arbitrarily shaped object like a tank or ship. I don't think they'll have the technology in the near future to create a metamaterial that bends light around any sort of vehicle or non-trivial object. In order to bend light around an object, the metamaterial needs to be anisotropic, meaning the index of refraction changes throughout the material in three dimensional space. While this can be done in the lab with a simple object, it would be incredibly difficult and expensive to produce an anisotropic metamaterial that would hide something large and arbitrarily shaped, and the methods to produce or mass produce such metamaterials are still a long way off. This is especially true with visible light, where the metamaterial must be built on the nanoscale.
In any case, this is still an incredible breakthrough. It hasn't taken them too long to move this technology from the microwave spectrum to the visible light spectrum, so progress may be fairly quick. Especially considering the huge amount of money the military is probably sinking into this for obvious reasons.
Here is some of the original metamaterial invisibility work on the microwave spectrum:
http://www.ee.duke.edu/~drsmith/cloaking.html
I actually worked in this lab for part of a summer writing a ray tracer to test these concepts. Maybe I should have stuck with this stuff...