Implementing portrait mode in Fremantle Messaging (i.e. email, IM, SMS, etc) will give the following advantages:
1. A user will be able to pull the device out of his pocket with one hand, and look at his incoming messages. Writing messages in portrait mode will be impossible without a vertical virtual keyboard, but it is less important as people check on messages way more frequently than write them.
2. Portrait oriented lists can contain much more entries than landscape lists, so a user can see more messages at once when quickly checking his email/IM status.
