Aims to encourage more high quality content on the site
I'm sure you must have heard of Google's YouTube Partner program, where you can become a partner and earn revenue for your videos (provided they are good). Apparently it is doing very well as they have over 15,000 partners worldwide. Since these people generate a lot of revenue for Google by driving people to YouTube, Google is now giving back to them by giving 500 of these partners $1000 each.
It will be in the form of store credit at B&H Photo, where these partners can get better photographic equipment for themselves so they can create better videos in future. Along with acknowledging those who are already on board, this should also encourage more people to become a partner and earn money for their videos.