Tucker's suit alleges that Apple's iPod/iTunes 'axis of funk' is an illegal monopoly, since the songs sold by the iTunes music store only play on the iPod; the suit also suggests that Apple has not done an adequate job of telling users that the iPod and iTunes content are not directly compatible with other digital media devices. One might argue that this exclusivity is just the business Apple is in with iPod and iTunes, but like I said, not a lawyer.
Now, I have nothing against silly iPod lawsuits on principle; they are, if nothing else, delightful blog fodder. I do wonder, however, what Ms. Tucker is thinking on this one. First off, you CAN get iTunes songs onto other devices; it's not necessarily straightforward to burn them to a CD and re-rip them, but it's doable. Second, y'know, there are other places to buy music (not Tower Records anymore, sadly). Third, there are, allegedly, other music stores and players. Is this really the same thing as rigging the browser wars in your favor? Just wondering.