From the Toronto Sun's Nosey Parker Blog, this was the most-played song of the 20th Century, with well over 8 million performances recorded by BMI.
Performed by the Righteous Brothers, produced by Phil Spector and co-written by Spector and the husband-wife writing team of Barry Mann and Cynthia Weil, You’ve Lost That Lovin’ Feelin’ was released in December 1964 and was No. 1 on both the U.S. and British pop charts by February 1965.
It is the only song to enter the Top 10 on the British charts three separate times — in 1965, 1969 and again in 1990.
In the decades since its release, everybody from Elvis Presley and Joan Baez to Telly Savalas and David Hasselhoff have recorded the song.
Nosey Parker offers so much on his blog post. Besides the info on the Righteous Brothers, there's good background on Phil Spector and a wonderful list of song titles written by Mann and Weil.
Thanks to Brodie, a Talk Left User, for the teaser. Talking about Phil, Brodie said this:
And it's most unfortunate, even a bit embarrassing, that one of this country's best musical talents ever -- and the guy partly responsible for creating the song most played on radio in the 20th C -- is now officially a convicted killer.