Neil Diamond, National Indoor Arena, Birmingham<br />Estelle, Custard Factory, Birmingham

Singer-songwriter Neil Diamond is basking in an Indian summer after more than 40 years of magical pop moments

A photograph can tell a thousand lies. The Neil Diamond merchandise stand sells T-shirts bearing the picture of the singer as a young, free spirit – the visual grammar tells you it was 1969 or thereabouts – with a guitar around his neck and flowing feathered hair wafting gently in the breeze.

Which goes to show, surely, just how much the pop industry has learned from Joseph Stalin. It's inconceivable that it hasn't been Photoshopped. The stats may say that he's just turned 67, but Neil Diamond has always been at least 50, right?

His songs, too, have surely always been old. It's impossible to believe that a disc jockey ever said, "And here is the new Neil Diamond single, 'Forever in Blue Jeans'." They've always been around, the staple diet of provincial pub singers, Butlins karaoke nights and wedding discos and jukeboxes.

Similarly, while the biographies may tell us that his Tin Pan Alley years were a rent-paying day job in tandem with an attempt to establish himself as a solo singer-songwriter, the Neil Diamond of the imagination spent the Sixties as a nice, respectful, balding Jewish boy locked away in the Brill Building, penning the pop songs for those crazy Gentiles to swing their hips to. He was around for rock'n'roll, but he never rocked.

He was, however, incredibly prolific. You forget how many great songs he's written. Just the other week I picked up a copy of Lulu's storming single "The Boat That I Row", and there on the old Columbia label is the word "Diamond". Tonight there's no room for "Red Red Wine", even in UB40's home city, although The Monkees' "I'm a Believer" does get a jazzed-up outing.

All of which goes to show that perception's a funny thing. Another photo, of much more recent vintage, tells another story: glance at the B&W pic of Diamond on the front of his latest album, and you'd think it was Johnny Cash. The hipster rehabilitation of Neil Diamond arguably began with Urge Overkill's cover of "Girl, You'll Be a Woman Soon", and Hot August Night, the 1972 live album from LA's Greek Theatre, has been belatedly canonised as his 68 Comeback Special, but it's Rick Rubin who has done the most to reposition Diamond, just as he did with Cash.

Neil Diamond's Indian summer is outshining his golden years. It began in 2005 with 12 Songs, a collection of songs that start as strummed demos before swelling into fully realised productions for the final minute. Its successor, Home Before Dark, is a transatlantic No 1 (amazingly, his first in either country), and in "Pretty Amazing Grace", he's scored his first British chart-topping single.

The revisionist Diamond, the rehabilitated Diamond, is mostly absent tonight (although he does play the Rubin material). With his comb-over and glittering jacket, he's a shameless Vegas cheesemeister: the smarmy smiles, the silently mouthed thank-you-so-muches, the wine glass and restaurant table he uses as props for "You Don't Bring Me Flowers", the delving into his schoolboy sword-fencing repertoire for those en-garde poses at climactic moments.

His audience, accordingly, is devoid of hipsters. This is the HRT generation. I've never seen so many people clapping at random, oblivious to the actual beat. But these are his people, and he unquestionably connects with them. A friend of mine calls Diamond "the straight Barry Manilow", but I prefer "a Dylan for the squares".

With that hammy rasp in his voice, he's nothing but sincere. Indeed, he's too sincere, too naive (and, to be fair, too American) to appreciate the puerile phonetic humour of the watersports connotations of a chorus that goes: "Love is all about 'we'."

An old romantic, Diamond always takes the most direct route, and often scores direct hits. I don't think I've ever seen so many people looking so happy as when "Sweet Caroline" hits the chorus. It's a mass orgasm which compels you to accept that, square or not, you're in the presence of one of the greats.

"Everyone thought: '... she's over.'" That's how Estelle remembers her status when John Legend lifted the west London singer/rapper from the dustbin, signed her, took her to New York, and jump-started her career. We're all the winners for it, even if we don't fully appreciate the fact. (The Custard Factory crowd is surprisingly sparse.) Sparkling in a chainmail mini-dress, Estelle Swaray is a far more likeable and charming home-grown alternative to, say, Beyoncé or Rihanna. Unlike her American counterparts she's funny, deliberately mishearing a heckle and replying: "What? I'm fit? Nice legs?"

It's a combination that worked on "1980", her debut hit that managed to make a hard childhood sound idyllic, and on the electro-soul banger "American Boy", one of the most irresistible radio smashes of recent years. "Here's my take on it," she says. "If you see someone and you wanna have sex ... go and have sex."