The West End Men who opened at the Vaudeville last night gave us a taste and a flavour of several great musicals - including Company, Phantom of the Opera, Rent, Chess and Les Miserables - in a concert format that reminded us, too, how very difficult it actually is to create new and exciting musical theatre.

While not a soft option, exactly, their show is a relaxed celebration of shows that took a lot of work to get up and running, a process that begins at Andrew Lloyd Webber's Sydmonton Festival this weekend with his musical play about Stephen Ward and the Profumo affair. Rumoured to be following Top Hat into the Aldwych Theatre, the show is written by Sunset Boulevard collaborators Don Black and Christopher Hampton and directed by Richard Eyre.

Fortuitously, Don Black's first ever West End lyrics, for the 1974 musical Billy at Drury Lane, are receiving a fresh airing right now at the little Union Theatre in Southwark. And those West End Men at the Vaudeville have a lot to live up to when they consider the star of that show, Michael Crawford. If Lee Mead can be casually dubbed a superstar by his fellow West End Men, that leaves no words sufficient to describe Crawford, or the impact he made in Billy. Based on the Billy Liar novel by Keith Waterhouse and Willis Hall, here was resounding proof, in the words of one of the songs, that "Some of Us Belong to the Stars" and some of us included Crawford from that moment on.

The first cast of Billy also included Elaine Paige, Diana Quick and Gay Soper as Billy's girlfriends, and Sam West's grandad, Lockwood West, singing a touching little nostalgic item called "It Were All Green Hills." I don't think Black has ever written better lyrics, and the show as a whole can be seen as a clear precursor of Billy Elliot.

Michael Strassen's production can't compete with some of the spectacular stunts Crawford pulled off at Drury Lane - he was obviously warming up for Barnum, which followed a few years later - but it's an absolute model of seamless, imaginative staging, stunningly well lit by Tim Deiling, with John Barry's score scrubbing up beautifully in a five-piece band led by Richad Bates. And yes, that's the same John Barry as the Oscar-winning one who wrote the James Bond movie theme and composed - with lyrics by Don Black, who also won an Oscar - the song "Born Free".

On a different scale altogether, and just around the corner from the West End Men, at the Coliseum, there's another striking new musical theatre production, The Perfect American. An old Scottish joke about two legendary American show business curmudgeons goes: "What's the difference between Bing Crosby and Walt Disney?" "Big sings, and Walt disnae..." The punchline will have to be amended now to "Bing sings and Walt disnae... except in a Philip Glass opera."

Not only that, Walt sings yearningly and lyrically in The Perfect American: Christopher Purves creates a wonderful portrait of the visionary cartoon film maker as a man wrestling with demons, confronting his death and longing for the innocence of childhood in Marceline, Missouri that he bartered into his work in a Faustian pact with himself.

Phelim McDermott's production is a brilliant and entertaining feat of showmanship, wittily echoed in the pink Disney suit he donned for the curtain calls. Philip Glass shuffled on for a warm reception, too, having spent a large part of the interval deep in conversation with his old friend Christopher Hampton.

Other familiar figures on the stage included Andy Warhol and Abraham Lincoln. As the first, John Easterlin cheekily waved at the front stalls as he loped louchely across the stage, while Zachary James' tall and bearded Abe was even more animatronically robotic than Daniel Day Lewis' version in the tedious Steven Spielberg movie, and a lot funnier. After these colourful historic exhibits, the West End Men at the Vaudeville look positively, and immutably, normal. And just a little bit boring.