Apple released iTunes 11.0.4 for both OS X and 64-bit versions of Windows (Windows Vista, Windows 7, and Windows 8) on Wednesday. The update includes two bug fixes.
Apple's patch notes:
This update fixes a problem that may cause iTunes to quit if you switch between wired and wireless syncing and addresses an issue that may require you to log into the iTunes Store repeatedly.
The patch is a 43.2MB download through the Mac App Store, and is available now. Apple's Downloads site hasn't yet listed the updates, and iTunes download for the Mac and Windows versions are showing version 11.0.3 as of this writing.