As far as I know, this is a feature that was in the previous Monster Hunter game, but will supposedly be expanded upon for the release of Monster Hunter 3. Word has it that the Monster Hunter 3 feature will allow you to record some of your battles. After that, you can upload these videos to Capcom servers. From there on out, other people can play the battles, and view them from multiple angles. Thanks to GoldenGun for the heads up!