Until the introduction of the iPad mini, the iPad had always had a 9.7" screen with the next step up being the 11" Macbook Air and the 13" Macbook, so giving the iPad a 13" screen puts it squarely in the Mactop market. Of course, we do not know if it will be rolled out an iPad or as a Macbook Touch, or something along those lines. I guess that will be down to which OS is eventually used.
So, what will it be? We just don't know yet but as soon as we do, we'll let you know.
Then there is the weight consideration and ease of use. 10" tablets can sometimes feel a bit cumbersome with many people choosing the 9" models for ease of holding and typing. Another thing to consider is, iOS is not Flash compatible whereas OSX is.
Apple are also looking to bring the iPhone into line with other smartphone manufacturers by upping the screen size to 5" from its' current 4". Again, nothing much is available on this front but things seem to be getting exciting over in Apple land.
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