It's not a VU - it's a texture update... typically the model stays basically the same, just with some little refinements and touches. I think Maokai's is mostly focused on his ability animations as well.
Ummm no, it is an actual Visual Update. Got it from here: http://www.surrenderat20.net/2014/11/1110-pbe-update.html
P.S. The updated Totemic skin's face looks like a baboon now O.o
Fair enough, you're probably right.
But when they were talking about it it really sounded like their main focus was on the ability animations... so skins that already have good visuals/textures probably won't see much of a change.