RockPack is a new app/service that has launched just recently - it enables you to subscribe to and create your own personalised video channels. If you have used Flipboard to create your own magazine and added articles, RockPack is pretty similar but it's for videos.
The app allows creators to create any type of channels they like, adding whatever videos they like to the channel. You can be as broad or as niche as you like - catering to all types of markets. So you can find channels by big names like IGN and Vevo or very small channels by one-man.
RockPack is actually a really great way to consume video on something like the iPad and iPhone. It wants you to explore more channels, more types of videos and in general just consume more content.
RockPack is free and available for both iPhone and iPad.