By Janet OzzardThe Marc Jacobs collection is a high point of the show calendar, and not just because the designer's front row is always packed with celebrities (this time: P. Diddy, Liv Tyler, Kristin Davis, Claire Danes, and regulars like Michelle Hicks, Anna Sui, and Helena Christensen). Jacobs has firmly established himself as fashion's bellwether, with an audience that looks to him to pluck out the prevailing trends and decree them relevant. This season, Jacobs is clearly feeling very mod. His show, set to churning punk rock (X-Ray Spex's "Oh Bondage" kicked off the soundtrack), was a color-splashed paean to pop, with overt references to the sixties space-age designs of Courrèges, Paco Rabanne, and Rudi Gernreich. Minidresses and jumpers in various patchwork combinations of orange, blue, beige, white, pink, violet, and red came dashing down the runway, detailed with felted seams and circle pockets and worn with contrasting hose and sweet little pumps. His silver fur-trimmed parka and boxy wool jackets are destined to displace the peacoat as next season's must-have outerwear.Even the evening looks kept the beat. Jacobs showed black and white satin minis with piped seams, as well as a few literally swinging dresses featuring ropes of giant sequins or slashed fabric sewn into a drooping bell. It was cheerful and chock-full of energy and color; but all the literal references to past fashions verged on re-creation, rather than the renewal for which Jacobs is justly famous.