Hi I nipped into HMV today to buy a copy of Guitar Hero IV World Tour for the PS3. I was told by a member of staff that they could not sell me the item as it was in tommorows (24/12/2009) sale. I then asked the manager if I could buy it at full price and he allowed me to have it for the sale price of £10 :)
Both Guitar Hero III and Guitar Hero IV are £10 on all consoles and this is apparently nationwide.
Happy shopping :)