A missed opportunity that perhaps went unnoticed

A while ago, Microsoft announced that DirectX would be coming to WP8. Today, surely, was the day to actually show this off, so why wasn't it? Microsoft just needed to show off 1 game running an impressive game on DirectX to really show off the gaming ability of WP8, as that's something we actually haven't seen much of yet (as opposed to every "new" feature they showed today).

Am I missing something here?