Create a site similar to Youtube.com or Putstream.com

We do not need tons of bells and whistles but we would like the design similar to youtube and optimized for mobile and tablet devices as well. The key to this is making the player for the videos easy, with options to add things like subtitles in separate files attached to videos (if possible), and make the player work on ALL devices with easy. There should also be the option to add video advertising to uploads like Youtube.