Apple (AAPL) investors, take note: The iPad is becoming a bigger part of the business faster than anyone thought.

The iPad's strong performance has led analyst Gene Munster to up his forecast for iPad sales next year to 21 million from 14.5 million. He called the iPad "the first Apple product that will be a success in the enterprise," according to AppleInsider.

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Apple shares surpassed $290 for the first time Thursday, perhaps in response to Munster's report, but closed at $288.92.

Businesses have indeed taken to the iPad with surprising gusto. But the device is also finding its niche with consumers, Munster said, as either a second computer for those who already own one, or a primary computer for those who can't afford a Mac.

An iPad as a primary computer? Yes, it can be done, writes Walter Mossberg of The Wall Street Journal, who ditched his laptop for an iPad when he went to Paris this year for a working vacation.

"With a few exceptions, I got everything done that I would have done with a laptop," he writes. "Yet I toted a lot less weight, enjoyed much better battery life, and had a computer that started up instantly whenever I reached for it."

Other analysts have reached similar conclusions about iPad sales next year. UBS Investment Research is expecting 28 million, and said the iPad is "adversely affecting the PC industry."

 

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Apple is positioning the iPad for strong holiday sales this month. Best Buy (BBY) will begin selling the device at all its stores this week, and Target (TGT) is rumored to begin sales next month, AppleInsider reports.

Munster thinks that Apple has completely dominated the tablet market this year, with about 94% of the 11.3 million tablets sold in 2010. (That, by the way, blows away the 3 million to 5 million in iPad sales that analysts had predicted for 2010 when the iPad launched).

Next year, however, Dell (DELL), Samsung and others will roll out their own iPad rivals, cutting into Apple's market share. Dell already sells a five-inch tablet, called the Streak, on its website and is showing off a seven-inch tablet at conferences.

Research in Motion (RIMM) is getting lots of buzz for the "BlackPad" tablet it is rumored to be developing. RIM could unveil the tablet next week at a developers' conference, The Wall Street Journal writes.

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