SPECIAL PREMIERE: Smokey Robinson and Cedric the Entertainer co-host this Grammy salute to Motown Records, honoring the 60th anniversary of the pioneering label from Detroit (which, in those days of US automotive production dominance, was known as Motor Town, a.k.a. Motown). Performers include some who, like Robinson, were there for the early glory days: Stevie Wonder and Diana Ross, for starters. Others include Fantasia, Thelma Houston, Boyz II Men, and such relatively unexpected guests as Litt