SAN FRANCISCO -- Apple's ( AAPL) fourth-quarter results after Monday's closing bell may show whether the recent innovation will validate a soaring stock. The company showed its mettle during the quarter with an impressive update of its blockbuster iPod franchise and the increasingly popular line of Mac computers. It also made a wise -- albeit poorly timed -- midcourse correction to the price of its iPhone, which propelled sales above 1 million in early September. As a result, Apple's stock has notched a series of all-time highs since mid-September. On Friday, the stock fell along with the rest of the market, but still managed to close at $170.42, just below an all-time high of $173.50 reached in the previous trading session. Analysts have helped fuel investors' expectations by steadily raising fourth-quarter earning estimates to an average of 86 cents a share on $6 billion in revenue, well above the company's forecast of 65 cents a share and $5.7 billion in sales. While the iPod and iPhone have enjoyed much of the limelight, Apple's growth story is predicated mostly on the Mac. In the previous three quarters, Mac sales have outpaced other Apple products by increasing their contribution to sales from 36% to 41%.