This would add 6% to our global unit sales forecast for the iPhone 4 (61 million iPhones instead of 58 million).

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If the next generation iPhone were to trigger similar quarterly growth rates for the remainder of 2010, the total 2010 iPhone unit sales could exceed our current forecast.

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The analyst has increased his forecast for smartphone unit sales for both this year and next year, but reduced his expectations for overall handsets.

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His current forecast is for iPad unit sales of 32 million this year, and 55 million next year.

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The Barclays analyst chopped his forecast for December quarter Surface unit sales to 700, 000, from 2 million.

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They also risk the burden of unsold (unit) inventory, purchased when higher sales volumes were forecast.

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However, there could be an upside of around 10% to our estimate for Motorola Mobility stock if the tablet unit sales increase at a faster rate to reach 12 million by the end of Trefis forecast period.

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We believe that the advent of tablets, especially the Apple iPad, could further slow down the PC market growth and forecast an average growth rate of 10% for the global notebooks and netbooks unit sales in future.

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He now sees total unit sales for the quarter of 26 million, up from 23 million. (Though he trims his forecast for the December quarter to 55 million units from 58 million.) He also adjusted his model to add in a December quarter launch for the widely expected iPad mini, noting also that he now sees an Apple television launch in the March quarter.

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