I was playing creative, just some few minutes after i updated to 1.4.5. I goed on, took the birch wood slab, couse i wanted to test out some few things. Birch wood slabs is brighter, than birch wood blocks, but only in the game, not in your inventory.

**HAVEN'T TESTED WITH OTHER TYPES OF WOOD**

EDIT: - I have tested it now. It seems like, that if you use your ''pick block'' key on 2 slabs together (to a full block) it would create the right block in your inventory hotbar, but by placing it on the ground will make it just like a oak wood