In 2007, Steve Jobs looked into the future:

“We’ve got two strong legs on our chair today — we have the Mac business, which is a $10 billion business, and music, our iPod and iTunes business, which is $10 billion. We hope the iPhone is the third leg on our chair, and maybe one day Apple TV will be the fourth leg.”

It’s a good thing Jobs used the word “maybe”, because the iPad has just sailed straight past Apple TV to become that fourth leg. During its first quarter on the market, iPad has already become Apple’s third biggest revenue stream. Despite supply constraints, the combined revenue of Apple’s two newest legs – iPhones & iPads – already exceeds combined revenue from the original Mac and iPod legs by 25%.