My iPod Nano (4GB) works just fine, and from what I have read, all iPods work with the PS3.
The trick is that like any USB storage device connected to the PS3, by default the PS3 is only looking for folders specifically named "MUSIC", "PICTURE", "PS3", and "VIDEO" in the first directory level on those devices.
If it can't find those folders in the first directory level, like the "MUSIC" folder, it will say "There are no tracks."
To bypass this, do not simply select the drive, or in this case iPod. Instead, highlight the iPod on the PS3, and press the triangle button to display your options for that device. Now select "Display All".
Voila, that will now show every folder on that drive regardless of what it's named, and if you are in the Music category in the PS3's XMB, it will then show every music file in those folders.
BTW: At least with my iPod, all the music is stored in the folder called "Music", which is in a folder called "iPod_Control".
The same goes for pics and videos. To see those, go to the appropriate category in the XMB, then select "Display All" for the device that is connected to the PS3, and it will then allow you to find those files.
Hope that helps you out, so that you can now use your iPod on the PS3. 👍