Well this is really annoying for me too, so I created a bug for it, since I didn't see it anywhere already.

The way I think it should work, is like Tag Clouds usually works, ie. show the most commonly used tags in the largest font, and the least common ones smaller. Unused tags would naturally not be shown at all. That would remove all these stupid "pre-installed" tags, thats crowding my Tag Cloud right now, and ruining the functionality (for me at least).

Here's the bug repport; https://bugs.maemo.org/show_bug.cgi?id=7781
Please go and vote for it, if you agree and/or have the same experince, so the Tag Cloud can be implemented the right way. Or chime in here or there, if you disagree.