At the Toy Fair pics there are two pictures of Toa of Light and it looks like he/she has blue arms!Could this mean Gali evolves into the toa of light?They even share the smae body design!

I don't think so. But maybe if she did she could have found the mask of light and put it on, But I think that it will be somone else.
K-9

I saw that and think it was just dark grey plus the lighting because I really doubt Gali will become the TOL because I say so and I am always right.