According to the blog iPodminusiTunes, Apple has blocked the new iPods from synching with third party applications (i.e. anything that isn't iTunes). The most significantly affected userbase in all this is the Linux community, who've been able to upload songs to their older iPods using free software such as gtkpod and Amarok for a while now. The tweak to the new iPod database files doesn't appear to be incidental either, with a number being added to the front of the database file causing the iPod to be exclusively tied to a single copy of iTunes. Fortunately, the problem isn't beyond a little bit of reverse engineering, so Apple's rather pointless meddling could be reversed given time.