Unless you have a newer iPod DO NOT upgrade to iTunes 7.5. It will trash the older gen iPods. As you can see from a Google search on "iPod error 1418" literally thousands of iPods have been trashed by this upgrade and Apple is remaining hushed about it.
When you connect an older iPod to the new software all will be fine till you reconnect it again. It will then tell you your iPod is corrupt or need to be formatted. At which time you say ok and it proceeds to recover it only to come back with a message error 1418 the iPod could not be recovered.
Complaints have been sent to Apple but their response is maybe you need to replace your iPod. Some believe it is a ploy by Apple to force everyone to get newer gen units.
My Shuffle was trashed in this way so as a warning to my fellow HF members. IF you have a first or older gen iPod and iTunes tells you a newer version is available, click not now and do not remind me again.