Medary.com

Kansas City's WDAF-TV reports that after the current Shuttle flight ends, the spacecraft will again be grounded due to external tank insulating foam which again broke off during launch of Discovery.

NASA will go back to the drawing board again.

Remember way back, early in the Shuttle program, the external tanks were all painted white? After a few launches, they decided they didn't need to paint them any more, in order to save weight.

I'm not saying that painting the tanks again would fix the problem, I'm just saying it's something to think about.