Liquid metal is a darker metal.
That's not true. It can vary in color, from very reflective, to ultra dark. It can be made to look exactly like aluminum, gold, carbon, steel, or given the look of burnt titanium. The aluminum you see on your macbook pro isn't even the way you see it from nature, it's altered and purified, which can also given the look of light to dark colors, along with anodizing to give any color of the rainbow.
If you were to brush an aluminum block the same way you would with a liquid metal alloy, they would look identical.
I do think it has something to do with Lion though.
A gray 15"MBP...oohhhhhhh I like!
But it does make you question why they went to the the gray style though.
Anyone else's apple website loading slowly? It's the same for all of my computers, while every other site loads fine.