I saw it discussed on BBC's Question Time, though I don't recall if any official source for the information was cited then. Possibly not.

Otherwise, an article in The Telegraph here CIA Admits Waterboarding Yeilded Vital Information goes into greater detail. According to Leon Panetta (director of the CIA) both so-called "enhanced" and other more conventional methods contributed to the full picture. I hear there has been some criticism of the Obama administration's seeming coyness about divulging this detail of the story, particularly from those who support the use of such methods.