Pen and touch computing are not competing technologies: you could have one or the other, or both, and the experiences would be complementary. Touch seems to have led to a much larger market than pen, which is still quite useful, just not something that everyone would wind up using like touch.

Would love to see Apple get into Pen computing, and this is one area where I think Surface could have really distinguished itself (including a digitizer on a low-end Surface RT, for example).