In last news conference, Bush concedes some mistakes

or
Dubya Outdoes Nixon: Mistakes Were Made

Business Mirror summarizes Bush's "ultimate exit interview":

Asked about mistakes he had made while in office—a question that once famously stumped him—Bush rattled off several examples, saying that he regretted his decision to focus on Social Security reform after the 2004 elections, a drive that proved unsuccessful, instead of first addressing immigration issues.

Bush also said hanging a “Mission Accomplished” sign on an aircraft carrier after the toppling of Iraqi dictator Saddam Hussein in 2003 was a “mistake.” He described the scandal surrounding the treatment of detainees at the Abu Ghraib prison in Iraq as a “huge disappointment,” as he did the failure to find weapons of mass destruction in that country, which the administration had claimed, based on faulty intelligence.

If Dubya had really wanted to come clean about his screw-ups, he should have started a lot earlier than just a week before leaving office. That sort of catalog could take some time to compile.