STAMFORD, Conn. ( TheStreet) -- Gartner took a stab at a 2010 tablet device forecast, and Apple's ( AAPL) iPad gets skewered.

Thanks largely to strong consumer demand for notebooks, worldwide PC growth is now expected to hit 20% this year, an upgrade from the 9% pace Gartner predicted previously.

Appearing on Gartner's report for the first time was the tablet category. Gartner predicts that 10.5 million tablets will be sold this year, roughly 2.8% of the total PC market tally.

Within that tablet category sits the Apple iPad, which debuts later this month.

"The most likely scenario for iPad sales this year is 4.2 million units ," says Gartner analyst Angela McIntyre.

That guess is slightly below the going Wall Street odds, which call for about 5 million iPads to be sold this year.

The lowball estimate points to the difficulty Apple may have in convincing people that they need another expensive device.

McIntyre says she expects the iPad to be an additive to the industry, meaning it it won't steal customers away from the netbook or laptop market, nor is it a threat to the smartphone sector.

Priced between $500 and $830, the iPad is not likely to attract a mass following.

"The price tag is fairly high for what it can do," says McIntyre. "We see Apple fans buying them first."

McIntyre also says the lack of a physical keyboard could limit its appeal to big groups like students who would find the touchscreen keypad troublesome.

"It will do well for email, for Net surfing and as an e-reader," says McIntyre. "It's an entertainment device."

-- Written by Scott Moritz in New York.


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