I don't see why not. You just need to copy the settings files from your .kde and .gnome (?) folders in the home directory to the home directory of the other system. Of course, you'll also have to make sure you have the same fonts, themes, and such installed, and you may have to reconfigure some things like device settings when you do. It's probably better to copy the rc files for each application individually than to overwrite everything at once, since there may be some apps you want to keep the settings for and others that just don't exist on the target system.
Personally, I just prefer setting everything by hand to avoid the conflicts that can arise from trusting external settings files. But that's just me.
