Yep, it has been rolling out slowly to all Nexus devices. They are probably still in the 1% or 5% mode right now, which is why so few people have it yet (I don't have it on anything yet). I am more interested in it on my N5 than the N10, but whatever... it will probably hit everyone in the next 4 or 5 days.
My Nexus 10 downloaded the update today while I was at work. When I got home I saw it and installed it. Very fast install. Everything seems to be fine.
Posted via a beautiful Ebony backed Moto X or the amazing Nexus 10 using the totally awesome Android Central App
When I take a screenshot now, the notification shade image's colors are all washed out. I think before 4.4.3 I remember the colors being vivid. (On the notification shade.)