The leather and diamond armor have separate textures in the snapshot. They can be the same color but it will only look like diamond at first glance, because of the different texture of leather compared to the elegant design of the new diamond pieces. The color should only be a problem from a far distance or to people new to the game or unfamiliar with the update, but they will see the difference at some point.
I think the extra layer should be invisible in the default pack.
I don't care about armor dye all that much unless they add it for iron and diamond (Yes you can paint iron and maybe diamonds). All you need to turn a dye into a paint is some kind of binder or such. Dye + glass bottle + clay lump = paint.
One dye I would care about seeing is invisible so I can see my player skin through the armor.
Wait, so if the layer only exists for texturepack makers why couldn't they just.. leave it blank? I mean it would still be there, only empty. Texturepack makers could add their stuff on the bonus layer if they wanted.
There was never a problem with it looking like the other kinds of armour. Leather doesn't have shine on it like the other tiers, and has buttons on the front in the recent updates. It didn't need some ugly brown layers.
I agree with making the second layer transparent by default, it just makes more sense.
I feel Mojang have just been fixing things that aren't broken, recently...
Yeah, they need to work on the animals breeding but no baby spawning glitch and some other multiplayer ones.