The difference between the Opening and Closing Ceremonies at the London Olympics: at the latter, rapper Tinie Tempah emerged from a flashy Rolls Royce and plugged his big hit alongside Jessie J; at the former, rapper Dizzee Rascal appeared in a section championing multicultural Britain and the democracy of the World Wide Web. Danny Boyle won that battle, and Dizzee, the East End boy singing Bonkers, became something of a national treasure.

Tinie Tempah appears on Dizzee Rascal's fifth album. So does Jessie J. And will.i.am and Sean Kingston and, unlikely as it might seem, Robbie Williams. Only one year on, but Dizzee has become a Closing Ceremony sort of guy. Most of these guest "duets" simply cut-and-paste a random but catchy chorus into the rap, but that is the nature of the modern pop collaboration: all the creative merit of a business handshake.

Elsewhere, the egoism, bragging and casual sexism that stains the hip-hop genre are increasingly becoming part of the show, a cynical philosophy that goes hand-in-hand with the music's all-out embrace of the commercial charts and shift away from the artistic vision that won Dizzee the Mercury Prize for his debut, Boy In Da Corner, a decade ago.