You "can" assign 2 different wallpapers, but just not with the today settings or "set as wallpaper" commands. They have to be included in a theme (.tsk) file. I'll post my tsk file with this as an example of setting up one a tsk with 2 different wallpapers for portrait/landscape.
Unzip the tsk file from the zip. Rename the tsk to cab and check out the setup.xml. The 2 other files are just renamed gif files.
Result looks like...
You can also set multiple wallpapers with WisbarAdv Desktop.
Glossy/Glass buttons will be the next thing I add once I get the fancy digits taken care of
