When browsing a very big version graph (several hundreds of tags/releases) the mouse wheel is actually useless: a single tick of the scroll wheel can jump 5-6 pages at a time: it makes you loose the point you were looking at and forces you to seek it again by using the keyboard (cursor up/dn or pgUp/pgDown), which is the only human-friendly scrolling method.
I think that a mouse wheel tick should never scroll more than 1/3 of the visible area under any circumstances.
Regards
ehm... any news?