CNet reports that Apple posted version 4.1.1 of iTunes (for Windows) on its site on Wednesday.
The new update "aims to remedy some initial glitches with the jukebox software that Apple released last week."
The update is available at http://www.apple.com/itunes/
Update: What's New: iTunes 4.1.1 includes improved performance when using your iPod, addresses an incompatibility with Windows 2000 and older third-party CD burning software, and improves support for non-standard mp3 files. Also, the "Keep iTunes Music folder organized" preference is now turned off by default.