The File Share is a file storage system in Call of Duty: Black Ops, where a player can store edited clips, custom private matches, or games they want others to view. Screenshots and full games that have been played by any player may also be added.
The File Share is able to store in-game theater mode footage made by the user, clips or screenshots from theater mode, and custom games. Currently, there are, at most, only six slots that can be used, and friends can access items in a player's fileshare and vice-versa. 30-second and under clips and screenshots can be uploaded to the Black Ops website and from there can be uploaded directly to YouTube without hassle, at the cost of inferior video quality.
Now you should be able to share your videos and screenshots with the world.