I believe he said most of our US Debt is owed to the good people of the USA and that we do not owe that much to China. I don't know if that is true..but I tend to believe the President. Owing money is not good..but I seriously doubt the Chinese Government is going to go crazy trying to get its money back. I am sure it was a loan in good faith, and it will be repaid in due time.
edited to say, this was when he was being interviewed by David Letterman, recently.