iTunes Updated, but iPod not synching

My iTunes was recently upgraded to the newest version, but now it says that i need to update my 30GB ipod and to just click on update in the summary tab. But the problem is that my iPod was originally formatted on my old PC, so now it can't update the iPod (only Mac-formatted iPods can be updated).
So the question is do i have to reformat my entire iPod and would i lose any data in iTunes?

any help is greatly appreciated!

I assume you have all your music in itunes.

Then all you would lose is some playcount data. When you reformat you cam resync and get all your pods tunes loaded up from itunes