Windows based iPod to macbook pro?

Download exPod (http://www.headlightsoft.com/expod/), connect the iPod and quit iTunes if it is open and let exPod copy the songs from your iPod onto the Mac and then use Disk Utility to format the iPod to Mac OS Extended and use iTunes to copy the songs back.
The whole erase and copy procedure is only necessary if you want to use that iPod solely with Mac OS X, as a Windows formatted iPod can be used with Mac OS X too, but not the other way around.

Btw, the above was for HDD based iPods like the Classic and such.

If you have one of the flash based models (Mini, Nano, Touch), exPod will still work, but I don't know how to reset them, though they should work with your Mac too.

Do you have any problems recognising that iPod on your Mac?