I think that may be part of it too, but I know it's not going to be a massive overhaul or anything. Nothing like Tiger -> Leopard

Even basic brush selection would be more advanced than MS Paint, in my opinion.

Here are a few other selections,

http://seashore.sourceforge.net/
http://paintbrush.sourceforge.net/...

I like Pixelmator better than GIMP, better usability, I feel.

It does cost $60 or something like that, but I thin it's entirely worth it.

http://www.pixelmator.com/

for users that are already using leopard, it wont be a huge change. there will be some minor updates, but it's really just like a Service Pack for Windows.

have you tried taking it into an apple store? they have on-site technicians which can help you with any issues...