In the latest beta build, the character creation preview gear has been updated.
Note that the sets merely serve to show a player what a higher level character of a certain class will look like.
It's not your starting gear. Many people claim the sets are upgraded Dungeon Sets from Vanilla.
All set previews are available. The only one I skipped was Death Knight, because their set hasn't been upgraded and is identical to the one you get in-game upon death knight creation (blame lazy Blizz).
Note that the backgrounds have been updated to better fit their respective races a while ago.