YouTube is curently having a beta version where it serve the contents in a lighter page than the usual one. This service is dubbed the Feather Project. It does looks good and uncluttered.
To use this service you have to be logged in on your YouTube account and go to this page: http://www.youtube.com/feather_beta to activate it.
Although.. I think that it would not help most of the internet user who wants to watch movies in HD and don't have bandwidth connection, to speed up their video streams.