even if you consolidate the library of the itunes when the ipod is connected, the itunes library will not detect nor recognized the ipod on your system.
legally speaking there is no way for you to migrate your playlist from 1 computer to another using your ipod. but technically speaking it is possible.
all you have to do is connect your ipod on a mac computer. on disk utility format the ipod into a windows format.
now reconnect your ipod to your comp again. it would resync itself to itunes and now you can use this to copy your entire library to from your mac to your ipod then from your ipod to your itunes on windows.
hope this would help you