There are (apparently cludgy) ways of moving your informationi about, but the impression I've had from this and other sites is that the iPad is more of a read/watch platform than a text-input one.
Unless you attach an external keyboard, the speed limitation of entering punctuation and numbers would be more of a deal-breaker for me if I were on the lookout for a very portable semi-work machine.
No speed limitation for me. I can type at full speed in landscape mode with the iPad on my lap. With the autocorrection feature, I can even take the sorts of shortcuts one uses when texting on old cellphones, but with a full qwerty keyboard. (No need to hit the shift key to capitalize iPad correctly, for example.)
Unless you attach an external keyboard, the speed limitation of entering punctuation and numbers would be more of a deal-breaker for me if I were on the lookout for a very portable semi-work machine.