What is the perfect pop song length?

Journalist Grace Dent asks whether the duration of a song can make it a hit or a miss. In Duration, Duration, Duration she speaks to record plugger Brad Hunner who has the difficult task of pursuading radio networks to play artists like Franz Ferdinand and where the duration is all important. Grace also meets Miranda Cooper, a songwriter for Girls Aloud and the Sugababes who writes to the 'ideal' radio duration of around three minutes.

http://www.bbc.co.uk/programmes/b01n0xpq