In reply to Arūnas.

It's a "googleguy" project, similar to that brandnew never seen before XML sitemap thingie. It will be pushed, no matter if it is ready oder useful for general public. People will have lots of issues with existing "lazy loading" features in all kind of plugins, but nobody cares about that, such issues will be closed with "contact third party vendor" in issue trackers, been there, seen that.