In all likelihood, Beatle Mania, Friday, June 9, at the Bluebird Theater, wont feature Paul, Ringo or George (or even Yoko, Sean or Julian -- thank goodness). But it will offer an evening of nostalgia for the Liverpool lads, courtesy of a band of wannabe mop-toppers who do a mighty mean She Loves Me.: Hailed as the ultimate Beatles tribute show,: Beatle Mania is a band that promises to cover all things Beatles, from the Ed Sullivan days to the later, less-clean-shaven days. It seems like impersonation bands are currently all the rage with a generation thats a little too young to remember the real thing: Neil Diamond, KISS and even Abba have their own alter-ego outfits. So its only fitting that the most beloved foursome in musical history should inspire a similar mock-up. Imitation, after all, is the most sincere form of flattery.