I've used Noteworthy (unregistered only) and it's pretty good. I just donwloaded "TablEdit" from ZDnet today. So far it looks OK. It allows you to mix & match standard notation and tab. I really haven't looked at the documentation yet, so I've just been "winging" it. It's reasonably intuitive but I'll post back once I've had a chance to try it a bit more. It looks like it might be able to export midi text files also.
Joe - I assume Dick & Max will post something about the software they're looking into???
Dave T