Does 10.0 have more code or less code? Does it boot faster? Shut down faster. Have more DRM? Give you more control over your own hardware?
Probably more code but a smaller memory footprint (less code in RAM at any given time). Boots and shuts down nice and quick, at least until you load in a million drivers and background tasks. Dunno about DRM, probably more. Control over hardware... eh, probably it's more restrictive, but that's a guess.
Caveat: Those comments are my opinions or guesses, not known facts.