[jerf]

"As the thickness and weight of the iPad decrease, it will become less cumbersome and more natural."

Try this: Hold your empty hands in a "tablet position" for ten minutes.

Even if the tablets managed to converge at zero weight (presumably helium is involved), their ergonomic problems do not go away.

[tewks]

Most users can read or draw on paper for more than ten minutes. The user can still place a tablet on his/her lap or desk.