I have an iPod with me and i used to use Apple iTunes to manage it on Windows. Since i now completely wiped out Windows on my laptop and i never logged in to my Windows on my desktop, i need to find a way to be able to manage my iPod on Linux.
I have heard about gtkpod project since a long time ago, but i never tried to use it until yesterday. There's a SlackBuilds script written by Robby Workman on SlackBuilds project, so i just use the script to build the package and it runs perfectly
At first, i'm a little bit confused with how it works, but after some testing (i tested by wiping all my music collection on my iPod and adding a new one), i finally managed to see how it works and yes, it does works on my iPod. gtkpod has supported many kinds of Apple's iPod products, starting from the first generation up to the fifth generation of iPod, including iPod Touch. To see whether your version or not, please visit this page.
In general, gtkpod has successfully replaced iTunes for doing basic tasks for managing iPod, but not to replace iTunes completely, especially if you want to access Apple Store, which requires official iTunes from Apple.
Good luck with gtkpod and have fun with it