For what it's worth news about updates to Windows Mobile and the development environment will be available at the Mix 2010 conference.
Until that news is released you may want to check out the Windows Mobile code application blocks. There is one application block that allows you to use the designer to specify your layout for both landscape and portrait mode. When combined with docking and anchoring that takes care of quite a number of layout scenarios.
It takes all the running you can do to stay in one place.If you want to get somewhere else,you must try to run at least twice as fast as that.