YouTube announced on their blog last week that they will enhance their HD options by adding full HD 1080p support. This will be available for new content, but they will also re-encode existing HD clips.

Here are couple of examples:
Pennie the Jack Russell (official YouTube blog demo).
Harry Potter trailer.

It’s an amazing showcase for next generation web quality, and a very popular example how to successfully deploy a performance optimized Flash fullscreen mode in combination with optimized H.264 encoding.

Read the full announcement on their blog.