Construct an indie rock matrix around those three bands and most of the rest of the 2007 headline acts would fit neatly into it, with the possible exception of Lily Allen and Scissor Sisters. Top billing in the Slam Tent, the under-canvas venue for the festival's dance music offerings, went to a pair of august American acts – DJ Shadow and hip-hop legends Wu-Tang Clan.
For the 2012 festival it's business as usual, at least as far as the main stage headliners are concerned. They are Snow Patrol (again), Kasabian (again: they headlined two years ago) and the reformed Stone Roses. Cast your eye down the rest of the top acts, however, and it's clear that something has changed since 2007. Here you'll find names that suggest something other than anthemic rock music or jangling indie guitar pop: names like Professor Green, Tinie Tempah, Labrinth, Major Lazer, Rizzle Kicks, Maverick Sabre, Chase And Status, Dappy and Jesse J, star judge of BBC One's The Voice.
Rightly or wrongly, neatly or not-so-neatly, each of these acts falls under the category "urban music", a label which wasn't even in common use in 2007. More important than the term itself is the fact that they are spearheading a vibrant British music movement which has already conquered the pop charts and is fast taking over an institution once ruled entirely by guitar bands: the summer rock festival.
If urban music has an epicentre, it's east London, particularly the borough of Hackney. It was there that Professor Green, real name Stephen Manderson, was raised by his grandmother, where he absorbed the underground sounds of jungle, grime and UK garage, and where he first began rapping at parties and open mic nights in clubs.
"I think there's a time for everything," he says. "It took a little while for our music to become prominent and to become accepted. I think that's happened now, for the first time ever. It used to be one artist that would get through here and there, but there was never really a breakthrough for the whole scene. But the music has become accepted now and it's a very prominent part of the charts."
Neither is that chart success anything to be scared of, he adds. "I think it's one of the best things that could have happened to the music. It doesn't mean that we need to necessarily water down what we do. I think people have just got a bit bored of the saccharine. There was so much manufactured music – and there is still – that was just churned out, that didn't have any purpose. I'm a fan of music with meaning, something with a little bit more edge and honesty, not 'Baby, baby, baby, I love you'."
Hackney-born producer and singer Labrinth, real name Timothy McKenzie, was just a few days old when The Stones Roses released their debut album in 1989. But as co-writer with Tinie Tempah of last year's massive hits Pass Out and Frisky, he's already topped the singles charts, and last month he joined X Factor winner Leona Lewis and another Hackney rapper, Plan B, on BBC Three's Project Hackney where they worked with troubled children from the borough. Last weekend, he and Professor Green were among the headliners at BBC Radio One's Hackney Weekend, a celebration of urban music which, ironically, took the form of a summer rock festival.
US star Jay-Z also performed, though it's a safe bet he was doing as much talent-spotting as he was lyric-spitting: his Roc Nation label has an increasingly Anglophile talent roster as he hoovers up British acts and producers like Chase And Status and Switch, one half of Major Lazer and the man behind the sample driving Beyonce's recent platinum-selling single Run The World (Girls).
Labrinth has a heavy-hitter in his corner, too: Simon Cowell. The 23-year-old was the first non-talent show signing to Cowell's Syco Entertainment group and has his own label within it, Odd Child. To his mind, then, the current crop of artists represents a new golden age of British music which, in its vitality, creativity and air of mutual co-operation, is comparable with the punk scene of the late 1970s.
"I think every decade it happens, where music has another cycle and something kicks in," he says. "I think it's just a moment, man, and hopefully some people are going to be made legends, just like the punk scene, and some people might disappear and have an amazing hit they can put into their scrapbook of amazing things they have done in their lives. I want to be in the legends side!"
One of the selling points of urban music to festival audiences is its connection with hip-hop, an easy fit with rock fans ever since Aerosmith and Run-DMC first walked out together at the suggestion of rock lover-turned-rap impresario Rick Rubin. Likewise, many urban acts are across rock music and comfortable enough with it to mine its more memorable moments for nuggets they can use. Professor Green, for example, built his top five single I Need You Tonight round a guitar lick sampled from Australian band INXS. "There's a lot of rock influence in my music and the same can be said for a lot of my contemporaries," he says. "So there is a crossover, I think, in the attitude as much as the music."
Not that listening to INXS was considered a proper pastime when he was growing up. "It wasn't that accepted to listen to rock music in the circles I hung about in at home," he says. "I had a lot of friends who were of Caribbean descent so I heard a lot of reggae, a lot of ragga. All the older kids on the estate were listening to jungle because that was huge at the time. It was the first music I got into."
Labrinth, meanwhile, confesses a liking for Nirvana alongside his love of Prince and old school American hip-hop.
"For me it was a foreign world that I didn't know about," he says of the grunge pioneers. "I didn't like it when I was younger but I liked the idea that I didn't like it, and I had to work to understand it. I think music has very much to do with your culture, what you're around and what your friends are into, but I wanted to like it for what it was good for, if you get what I mean. When it really clicked, I was so happy because I found something fresh for myself that I was into and that was important for me."
But as well as the summer rock festivals bringing urban acts into the fold because the promoters think they're hot, there's a growing awareness that the tastes of festival goers themselves are also changing – and not just because urban acts sample INXS or know what teen spirit smells like.
"What has changed in the last five years is that everyone listens to everything, and I think that's where the transition has been – people's horizons are a lot broader than they used to be," says Professor Green.
Labrinth makes the same point. "I remember speaking to one of my friends about it. He's a full-on rocker but in the past year he's really opened his tastes in terms of what he wants to listen to, so I think music is definitely changing in terms of what people are down with. I feel like we're losing our scenes. There's just one big scene. For me, I just make music, man ... I wouldn't really call myself urban. My set is mixed with urban, but I think it has enough in it to feed a rock crowd."
Among the coming masters of the rock festival he may be, but there are some of its traditions that Labrinth is only now taking fully on board. The need for sturdy footwear, for example.
"I was a festival rookie last year and I'm still getting over it," he laughs. "I'm still making the same mistakes – I still wear white trainers! I bow my head in shame for doing this, but at the Hackney Weekend I had my Union Jack wellies on."
He's promises not to wear them in Scotland, though.
T in the Park runs from July 6-8; see www.tinthepark.com for full line-up details. Televised highlights, including Professor Green, begin on BBC Three on Friday at 8pm
