Thanks for all the feedback, everyone! We're happy to answer any questions you have in this thread--ask away. We're very excited to show what we've been working on, and we can't wait (sorry) to show you all where we're headed in the future.
All of our trailers are actually being streamed from YouTube. We're using the YouTube API on the website to build a nice HTML5 player, and then in the app, HTML5 plays using the native player.
I always assumed you could not do that as the terms of service say
You agree not to distribute in any medium any part of the Service or the Content without YouTube's prior written authorization, unless YouTube makes available the means for such distribution through functionality offered by the Service (such as the Embeddable Player).