Activision and RedOctane has been working furiously to deal with issues Guitar Hero World Tour players have been having with their over and under-sensitive drum kits, and to that end they've released a Guitar Hero World Tour Drum Tuning Kit, as promised back on Tuesday. The kit takes the form of a 10MB PC application, which features a simple interface that allows you to assign a sensitivity level from 1-20 for each pad and the pedal.
To interface with your drum kit, however, you will need a midi to USB cable, which you most likely don't have. RedOctane provides a link in their support centre article where you can submit a ticket for information on how to receive said cable. Not quite as good as having all peripherals work out of the box, but at least they're trying.
Guitar Hero World Tour Drum Tuning Kit [RedOctane - Thanks Nick!]