I believe you can, yes.
Guitar hero World tour is called Guitar Hero World Tour because you go around the world in your concerts.
It depends if the Guitar Hero 3 songs were released as DLC on GH: World Tour. There is no way to directly import songs from Guitar Hero 3 onto World Tour.
No only guitar hero world tour P.S. you can only play the drums on guitar hero world tour
No you cannot
No you do not.
yes you can play guitar hero world tour, guitar hero metallica and guitar hero 5 with rock band drums!! ;))