less, for sure ..
It may on your machine, but it certainly doesn't on mine. The fact that YouTube HTML5 videos currently crash the browser on 4 different machines says enough to say that it's not as stable as Flash in my environment.
Adobe's Flash is useful, when used for the right thing. Businesses need to capitalise and gain from current not future. Until DRM and such is sorted, I don't see mass migration of content to the platform.