I never use my N900 for portrait either, i have auto rotate for the phone that all. howver Sygic navigation also works in portrait mode.

I think you may have misunderstood, i meant the the brodit swivels so that the phone is upright in portrait mode, but that would only be of any use for the phone application (well and the web browser and sygic navigation)

P.s. I have the same firmware as you assuming it is the 203 variant.