Flash5, Flash MX and Toon Boom

I really like how Flash works.
Its one of my favorite programs.

I am pretty good at Flash 4.
so when 5 came out, I purchased a lot of books on how-to.

In addition to it being very different from 4, I wanted to learn Flash properly (clean up my action scripts, etc).

so now I familiar with flash5.

I had been using up to now a PC.
I recently bought an apple (yay!) and with that, my husband got me Flash MX.

I admit I haven’t played too much with Flash MX, so my appologies if my questions have obvious answers.

what are the main differences between 5 and MX?
I had heard that MX came about because of a lawsuit and infringement of pallete design.

Is there a book that you recommend that discusses the differences?
Or is it best to get a how-to flash MX book? One that goes over all the basics.
Is the program that different to merit getting such a book?

I don’t know if the differences I see are because of my change of computers (i,e programs on a mac tend to have a different interface than those on a PC).

also, I was wondering about toon boom.
I haven’t played around with it so I am unfamiliar with it.
Is it the same as flash, but by another company?
Is it more geared toward animation? I imagine it is.
Is it worth getting?

thanks for your input.