if you're doing video work (and it has gpu acceleration) you should get a amd gpu.
But ya.All depends on your budget...
$100: AMD 7750
$150: AMD 7770
$200: AMD 7850
Actually, more software for video editing uses CUDA from Nvidia. This is especially true if you are using Adobe products. AMD will have no acceleration (I have tried both Radeon and Fire Pro cards). If I were in the market for a video card right now though and it was mostly for games, I would go with the 7850. If you are editing enough to warrant a compatible card, go with a 660gtx. I actually used a 7850 until I started editing more often and then sold that and bought a 570 gtx (you can get them for around 200 bucks now).