With the exception of the weather widget and the launcher widget, from what I've seen elsewhere, it appears to be difficult to get M2D to relocate elements on each tab to adjust to landscape.
This may be because some of the POS and RECT attributes that currently only have portrait info will actually only accept or use portrait info. It may also be because .map files for certain screens may be set up once to maintain the structure and we may have to delete them to have xml changes take effect (much like modding the Samsung keyboard). Or it may be because certain missing item id's address landscape attributes.
Ultimately, I would like to:
1. shift the "Call history" and "Calender" on the home screen to the right, next to the clock in landscape.
2. Shorten and broaden the envelope on the email tab and move the new email and counter buttons to the upper right of the landscape.
3. Have the people tab act like the launcher tab in landscape (simply redistribute the contacts across the screen).
4. Either shift the links under the launch browser to the right, keeping the same browser icon, OR resize the browser icon and center everything in landscape on the Internet tab.
5. Adjust the messages tab much like the email tab in landscape.
6. Center the preview and camera/movie buttons on the camera tab in landscape.
7. Stretch the Maps Search field across the screen in the location tab in landscape.
8. Redistribute the buttons in the settings tab to two columns in landscape.
9. Generally fix the music tab in landscape (this tab is totally wacked).
Anyway, just thought I'd share my vision and to-do list. Heck, at this point, I'd be happy if I wouldn't have a bunch of blank screens and if I could get M2D to stop autorotating to portrait everytime I close an app.