Also, a good way to understand it is by this, for example, open a 3D FPS in your computer, set in on 640x480 and play a game, now set it to 1280x1024, what happens? Your gun and enemies and everything is the same size (their size is resolution independent), GUI elements ARE resolution dependent and hence why they look MUCH smaller at bigger resolutions while the 3d renders retain their same size, except 1280x1024 looks much cleaner.
This means, the GUI in Leopard can be set to be the same size across ALL resolutions, higher resolutions will look more detailed, I imagine this specific size can be completely customizable AND I also imagine this feature can be turned off as well.
It is a rather cool feature, but it doesn't mean you can run a 1280x1024 LCD run at 1024x768 and retain quality, you'd have to invent a new non-pixel fixed display technology to achieve that 😛 like CRTs.