i'm curious if there's any reasoning to 300 grams. I don't have an iPad, but i've used one, and it seemed fine to me - i guess over a long period it could become uncomfortable.
I read my iPad2 in bed pretty frequently, it's just heavy enough that resting the weight of the device on a single edge on your chest will become unpleasant rather quickly.
As an extra datapoint, a Kindle (170 grams) is trivial to lightly with a few fingers. It's no substitute for a tablet, but when all I want to do is read a book I love it so much more than any heavier, more capable device.
