File Type is not supported by the ipod

I'm having the same issue. I sync'd my iPod yesterday just fine, but after updating to iTunes 7.2 and purchasing a iTunes Plus album, some of the "old" iTunes tracks are not syncing (the album I just purchased sync'd fine). These tracks play fine in iTunes. What I find really strange is that while some tracks won't copy over, some from the same album copy just fine. They were all purchased from the same computer so authorization shouldn't be an issue.
I'm wondering if there shouldn't be a software update for the iPod to go along with iTunes 7.2, but iTunes says no.

iMac 24" iTunes 7.2 iPod Video 1.2.1 Mac OS X (10.4.9)

Same problem here... I tried to sync my nano (1st gen). That failed. So I forced a reset.
Now the iPod can be synced but several songs are not loaded ("file type not supported") onto the iPod though they play back fine on my Mac...

iPod nano Mac OS X (10.4.9)

Ditto - must be something to do with iTunes 7.2, since I can load the same songs from my wife's computer, where 7.1 is still active.

In iTunes, drag the songs to the desktop.
Then delete them from iTunes.
Re-add the files back in to iTunes.

It's not necessary to save the files to the desktop, you merely need to remove them from your library and re-add them to iTunes. Why this happens is beyond me. I would think a company that prides themselves on thinking things through would be able to predict these problems before they occur but I guess they're getting sloppy. Too focused on their margins, I guess.

Word to the wise: If you don't have to update your iTunes software, don't. Everytime I do, I encounter similar problems.

As the software gets more complex and people want more features it becomes exceedingly more difficult to anticipate and test for every possible situation/problem. In the case of iTunes Store songs that were burned to discs and reimported, since this is in effect breaking the Fairplay copy protection it is reasonable that Apple programmers would not anticipate this problem.

At least there is a viable workaround that requires little effort.

I don't believe this has anything to do with being focused on margins, it is just that programming is hard. Try it sometime.

And the only problem I've had in any of the iTunes upgrade is the same one others were having with iTunes Plus upgrades...but it is now fixed and all my EMI songs are upgraded.