Here is a quote from YouTube’s website:

You may have noticed that we’re now giving you the option of watching some YouTube videos in higher quality. We’re making these streams available on certain videos, based upon the source file uploaded to us, and over time you’ll find a greater percentage of the library is available to view in higher quality. This feature applies to all eligible videos uploaded from the YouTube community, and is not restricted to partner content, so everyone can enjoy this upgrade.

At last, YouTube has opened their eyes to the world of High Def! But there comes some issues, along with this superb announcement. The upload speeds will triple, maybe even quadruple, with the video files increasing in size. But in return for this painstaking wait, you can get videos that you can actually enjoy on your high def television B) . But not only does this increased video file size affects upload speeds, it affects download speeds as well. So much for 1-2 second video starts :( . But I figure you have to give some to get more.