Letter/A4 Sized iPad?

I have been saying for awhile that Apple will have no choice but to come up with an A5 sized iPad/Touch. Now, with the new iPad 2 having been trimmed down in weight and thickness, it occurred to me that it portends a letter/A4 sized iPad. The current iPad users will start to find its current size to be too confining. The engineering that makes for the lighter weight and thinner iPad 2 would make the larger iPad a natural extension. The current iPad is designed to be used two-handed or to be placed on the desktop or laptop. It could be used on the go in a cradled manner. Either way, a larger sized iPad would offer more real estate without losing portability.