Activision and Logitech have announced a partnership through which Logitech will create "premium" instrument controllers for Guitar Hero: World Tour. It's not exactly clear from the press release, but we believe this means that Logitech will sell nicer, more expensive versions of the stock Guitar Hero instruments, not that they're producing the ones that come with the game. The new instruments will be fully compatible with World Tour, which basically means that the drums will have the appropriate number of pads and the guitar will have an insane touch pad on the neck.
It's not too much of a surprise, after Rock Band got its set of expensive drums, for Guitar Hero to follow suit with "premium" instruments. For extra instruments, this may not turn out to be a bad thing, since Logitech generally makes high quality peripherals. It seems like an uncomfortable position for RedOctane. They started out making music-game peripherals, including those for Guitar Hero, and moved into publishing. Now Activision owns them and publishes Guitar Hero, and Logitech is making instruments.