I am not sure whether IBM or Microsoft where once the greates companies by market capitalization no matter how successful they have been. But Apple is today (Market Caps in USD - AAPL: 337.2B, XOM: 330.8B, MSFT: 202.8B USD,CSCO: 75.53B, DELL: 25.76B, IBM: 194.1B, GOOG: 177.3B) and nothing beats the present.This year Apple will be more profitable than IBM and Microsoft, while having higher revenues than MSFT. The reign at the to will not last forever, but given the history of where Apple is coming from, it is not a small achievement. And since they are still growing and creating new markets which did not even exists, they will be on top for a long time to come. They have a new iPhone and iPad lined up this year, plus they are curtailing existing markets for Samsung and Android. There is talk of them hitting 1 Trillion USD in Market Cap before end of next year.