Fresh from being anointed a Godlike Genius at this week's Shockwaves NME Awards, Dave Grohl celebrated with a roaring two-hour set with his recharged Foo Fighters at Wembley Arena, still a dismal dive despite the major refurbishment which put the entrance at the wrong end. However, Dave basks in the reputation of being the Nicest Man in Rock and a thoroughly good egg (Lemmy says so, and nobody argues with him), and he successfully flooded this unprepossessing shed with good vibes mixed with shattering quantities of decibels.

I didn't realise how much I liked dirt. Especially New York dirt. I was going to do a rant about boutique designer hotels, which seem ubiquitous in Manhattan. Major case in point: the Gramercy Park Hotel, where I used to stay in the Nineties and Noughties. It was independent, a bit scruffy, with a great bar full of artists and rock'n'roll types and other degenerates, a perfect location and cost about a hundred dollars a night. Last time I looked it had been ponced up – fish tank in the reception, a Buddha, fancy doorknobs and good-looking but no doubt useless staff. Clean as a whistle.

Bob Geldof only shuts up in the end because a plane he should be on is imminently taking off for India, and he is still in his local South London pub, refusing to let a heavy cold stop him from talking like others drink - with unquenchable relish. He is in passing promoting his new album, How to Compose Popular Songs That Will Sell, a lesson Geldof could have given with conviction during his old band the Boomtown Rats’ pomp between 1977 and 1980, when their first nine singles hit the Top 20, climaxing with consecutive Number Ones “Rat Trap” and “I Don’t Like Mondays”. The way those achievements have been forever dwarfed by his marshalling of global compassion to save countless Ethiopians with Live Aid is something he can live with.

Gang of Four vocalist Jon King remembers the last time he was in Heaven – the venue, not the celestial aftershow party. It was the night of the Great Hurricane of 1987 and as he walked down nearby Villiers Street later that evening two trees blew past him. "It was a gusty night," he recalled onstage with a smile last night. The question was could the latest Gang of Four line-up blow up their very own storm in WC2?

The idea of "selling out" has clung to popular music, and indeed most art forms, for a long, long time. In our postmodern techno-consumerist society it's an increasingly outdated and irrelevant concept. The book Faking It: The Quest for Authenticity in Popular Music by Hugh Barker and Yuval Taylor shrewdly takes the whole notion of selling out to pieces, from the blues of the early 20th century to Moby's deconstruction of those blues decades later. Or rather, it simply points out there was never such a thing as a core purity from which anyone could sell out in the first place. Really, Barker and Yuval say, there's no such thing as authenticity and therefore no such thing as selling out.

The annals of rock’n’roll are littered with complacency, fading stars, and acts who’ve had it and then lost it, forever. So, after 20 years, what makes the Manics different? How come they’re still turning out hit albums? Possibly it’s their hand-on-heart, Welsh-valley principles. Maybe it’s the way they find libraries as interesting a subject as love. Or perhaps it’s the way that they keep recovering from the brink of near self-destruction. Listening to them last night, though, something else became clear.

If you’ve never heard a Gang of Four track, you probably still know their music. Their influence is all over the Red Hot Chili Peppers, Bloc Party, Franz Ferdinand, and R.E.M to name but a few of their fans. And that's just the musical legacy. Because Gang of Four, primarily active from 1978 to 1983, if they changed anything, changed the way bands considered the role of rock music. Paul McCartney may have wanted to fill the world with silly love songs, but Andy Gill and Jon King wanted to jam the airwaves with social injustice, war and disconnected lives.

A freezing winter of discontent, a Labour party hell-bent on making itself unelectable, controversial warmongering and record levels of inequality. It may sound like yesterday’s papers but these themes were also addressed by iconoclastic post-punk artrockers Gang of Four in the late Seventies and early Eighties, more than 10 years before the Manics brought agit rock to the masses. Next Monday Gang of Four release Content, their first original album in 16 years.

Over the last 25 years I've done a lot of DJing, or at least playing records in public that, occasionally, people have been refreshed enough to dance to. I've done sets in all manner of scenarios, from nightclubs to house parties, to gallery events, to a Finnish festival in front of thousands, to a Balham comedy club. The last used to pay me £300 a night to play the same cheese and predictability week after week, but one evening when I put on "Fools Gold" by The Stone Roses and my heart sank with boredom, I knew it was time to get out, £300 or no £300.