I had the same problem last week. I called Apple support, and they told me to disable iTunes Match on both my PC and iPhone. After I did, the playlist created on the iPhone synced with iTunes.
Originally Posted by -ND4SPD-
The tech said he has received calls about this issue before, and Apple supposedly knows about the issue. When I asked him if the problem had been documented anywhere, he said he didn't think it had, but there had been some discussion on the Apple support forum.
If you are using iTunes Match, you might want to disable it and see what happens.