Back in my radio days we referred to classic rock as "album oriented rock", or "AOR". When listening to Little Steven's Underground Garage, I heard him mention that Sgt Pepper and the summer of love basically set the stadards for that. True, so true, that in the 70's, many people were more likely to buy the whole album. There were few-to-no throw away cuts on rock albums, but I not realize Sgt Pepper began it all, even before the 70's. Was Little Steven right? I thought he was. Any thoughts, feelings, etc...? Thanks for your input! : )
Interesting topic! I think it's quite reasonable to argue that Sgt. Peppers set the course for AOR albums. After all, there were no singles released off the album to promote it (standard in the US - though not in the UK where the Beatles didn't want their fans to have to buy songs twice). You'd be hard-pressed to find a hit pop/rock album in the U.S. prior to Sgt. Peppers that had no singles released off it. The Beatles wanted people to experience the album as a single work of art. In the UK, they were able to convince EMI to release the album without any discernable vinyl groove gaps between the songs on the album (making it very hard to place the needle down on your desired song and thus encouraging the listener, and radio stations, to play the entire side).
It's also pretty much the first rock album to print the song lyrics on the cover, too.
The Beatles are single-handedly responsible for the rise of the the album over the single, and while they had been moving in that direction since Rubber Soul, it was Sgt. Pepper that was truly the first album as a fully integrated musical statement. The White Album was also the first double album. I also seem to remember that Sgt Pepper was the first gatefold album, but I may be mistaken on that, although I can't think of another before that. It was certainly the most artisitic album package to date, which inspired countless bands to use their covers to extend their artistic vision beyond the music.