Does it make good strategic sense for Apple to be a competitor in the computer, personal media player, smartphone, and tablet computer industries? Are the value chain activities that Apple performs in computers, personal media players, tablet computers and smartphones very similar and "compatible" or are there very important differences from product to product? Which of the four products lines-computers, tablet computers, personal media players, or smartphones-do you think is most important to Apple's future growth and profitability? Why?