According to the Wikipedia article, the first two editions (1973 and 1974) were on NBC, with the special not seen on ABC until the 1975 edition. Also, I read somewhere that Dick Clark was not in Time Square the first year, and someone else was there to help count'em down.bpatrick said:...I know that the first New Year's Rockin' Eve aired on Sunday, December 31, 1972--on NBC, and I think it was called "Three Dog Night's New Year's Rockin' Eve." That night, ABC had the Sugar Bowl starting at 9 (ET), and many of its affiliates, which carried Lawrence Welk anyway, carried his one and only New Year's Eve show separate from his regular show (I feel certain CBS had Guy Lombardo).
The next year, New Year's Eve fell on Monday; NBC had "The Tonight Show" as usual, so "New Year's Rockin' Eve" switched to ABC, which was doing the hodgepodge "Wide World Of Entertainment" format at the time. I think that's when it was first called "Dick Clark's New Year's Rockin' Eve."
http://en.wikipedia.org/wiki/Dick_Clark's_New_Year's_Rockin'_Eve_with_Ryan_Seacrest