Noa, if you work from keyboard, as it`s usually the fastest way to edit, you may find that Adobe changes keyboard editing behaviour with almost every release from ground up. Basic mouse dragging and timeline movement stays the same, though.

The first thing I did after installing CS3 was assigning all my favorite keyboard shortcuts, it might take a bit longer the first time trying to find all the right actions but as I only need to do this once I really don't see any issue here.
Because I use Norton Ghost to do a fresh install every six months I can go on for years without even worrying about it.

Changing shortcuts doesn`t matter, it`s different behaviour. But if you don`t have problem with that, good for you.