@sopwith: I think it has to do with the source documents. A 10" pad can reproduce A4-sized documents in more natural fashion. Web pages were also designed with that size in mind.

Yes, a small screen with a high enough pixel density of course can reproduce all the details; but it will still be physically too small (much higher dpi than originally intended).

So in the end, I guess it depends on what contents you're planning to use the tablet with.