Not sure if this is nationwide, but it's currently on offer in the Fulwood Preston store:
Movies DVD chart: Top 10: £10
Artist Album Chart: Top 20: £7
PS3/ XBOX 360 chart: Top 10's: £25
This offer lasts till the 21st August with exception to 'The Ashes 2009' which is only on offer till the 14th.
Some good games in the top 10. Just picked up 'Call of Juarez 2' on the 360.