I don't understand the responses from some of the community in regards to this. Do you deny that there is a use case for portrait mode?
One handed operation is key to productivity when one wants to check quick status of calendar, email, etc. and quickly respond to a message or reminder. Learning Linux isn't going to let me be able to manipulate the device any easier in landscape mode. And landscape mode is great for web browsing, gaming, typing email, remote admin, etc. but you can't deny that there's a portrait use case.
I'm an E71/N810 user as well. Being able to pull the device out to check messages, calendar events and to answer calls one handed is part of what makes the device great. Walking around having to use two hands all the time in landscape mode is not efficient or productive for short tasks.