I agree to that.

I do understand that this device teaches us to concentrate on its power in landscape mode, but looking at this device generally, since this is also a communication device, why not Maemo founders make it easier for users to send SMS in portrait mode too since texting is usually done in a portrait mode approach?

N900 is a different thing since it is a mix and a confusion between tablet pc and smartphone.

Looking at its awesome dial pad, I think SMS is more often utilized than dialpad. I don't think there will be no reason why it shouldn't be implemented.