I was watching the end of day 1 press briefing and actually with just the live cameras they spotted 3 separate pieces of debris. That specific one was classified as "what the hell is that thing?"

A small piece of tile got chipped near the front landing gear cover. They said they believed it to be around 1.5 inches big.

And the last item, which by the way I totally predicted to my buddies, was the bird flying around before launch got hit by the main fuel tank before the shuttle completely cleared the tower.

Hopefully they were wrong about the tile chipping away, but either way it's looked like a very small piece compared to the last incident.