Miller Brewing Co., Milwaukee, is celebrating the "50th Anniversary of Rock 'n' Roll" with eight commemorative beer cans that feature Rolling Stone cover shots of Elvis Presley, Alice Cooper and other acts. The promotion, a joint effort between the brewer and the magazine, ties rock's anniversary to Presley's debut at Sun Studios. Other cans depict Blondie, Bon Jovi, Def Leppard and Willie Nelson, as well as the guitars of Eric Clapton and Joe Walsh. The campaign was generating lots of buzz, but raised at least one dissenting vote. There are no black artists depicted, as a Syracuse University professor of pop culture pointed out to Associated Press.A Miller spokesman who was also quoted by the news service said the company started with a broad wish list, but its choices were limited to Rolling Stone magazine covers. And Rolling Stone, having debuted in 1967, wasn't around for the birth of rock 'n' roll when many influential black artists were active.