In a recent statement from Steve Jobs, he stated that a "7-inch tablet are too small for a pleasant touchscreen experience", likely referring to the Samsung Galaxy Tab and the BlackBerry PlayBook.
“7-inch tablets are tweeners: too big to compete with a smartphone and too small to compete with the iPad,” said Jobs, adding that competing manufacturers were struggling to meet the price point of the iPad, which starts at $500. Both Samsung and RIM have not announced pricing on their tablets, but are rumored to require a 2-year contract to meet the price point.
It's meaningless unless your tablet also includes sandpaper, so that the user can sand down their fingers to around one quarter of their present size," Steve said. "Apple has done extensive user testing and we really understand this stuff," he said. "There are clear limits on how close you can place things on a touchscreen, which is why we think 10 inch is the minimum screen size to create great tablet apps."
During its earnings call, Apple stated that it shipped 4.2 million iPads during the 4th quarter. At this selling rate, Bernstein Research noted that iPad adoption rates are the fastest in electronics product history.
"No tablet can compete with a smartphone. And given that all tablet users will already have a smartphone in their pocket, giving up screen area to fit in a pocket is a bad trade-off", Jobs said "Seven-inch screens are 45 percent as large as an iPad"