@ dow: The zoom function disables itself if your screen resolution is too low to handle it. You must have 1200 horizontal pixels to see 200% zoom, 1800 pixels to see 300%. It looks absolutely wretched if it tries to scale beyond your screen's capacity. It would stop at the screen's side but continue scaling vertically distorting the play area. Scaling to non-multiples like 150% also has terrible results, some pixels are doubled while others aren't.
Yes, I use 1024x768 resolution, so this is the reason. However the (about) 170% option could be still useful because now I have to use the fullscreen option which enables similar scaling mechanism on LCD monitors (plus it's annoying to switch the resolution every time you want to see desktop, plus some minor issues). So I wonder if the scaling quality (of MMF?) is much worse than the one LCD is using.
And, of course, the question how many people around here is using 1024 resolution to bother you to implement it