Hard to think of a better way for the Beatles' Paul McCartney to celebrate his 80th birthday than by singing “Glory Days” onstage with Bruce Springsteen or being serenaded by some 60,000 well-wishers. That's right, the “cute Beatle” turns 80 on Saturday, June 18. It's one of those cultural milestones that brings a sharp intake of breath — has it been THAT long? — along with an appreciation of what he still has to offer.