Just spotted this, seems like a great deal if you don't already have GH:WT!
(I've put £49.99 in the price section as that's the PS2 which is cheapest of all the versions, but I guess most people will got for the 360/PS3/Wii versions which are £69.99/£69.99/£64.99).
In the all-new Party Play mode, players can now jump in or drop out of gameplay seamlessly, without interrupting their jam session
Play with any in-game instrument combination in any game mode - multiple vocalists, guitarists, bassists and drummers
Features new in-game artists and rock legends
The entire set list is available from the beginning
Software compatible with Guitar Hero World Tour peripherals