"The federal government will unveil a new $20 bill that will introduce a predominant but subtle color into the background, marking the first time in modern history that a U.S. bill will feature a color other than green.
According to the Treasury Department, other changes will include new images of Andrew Jackson and the White House, as well as other adjustments that are being kept secret. The official unveiling will take place on March 27, with the new bill entering circulation in the fall." - from CNN Money
As long as the new bills don't look like Monopoly money, it's fine by me.