Apple released iTunes 11.1.5 on Wednesday. The maintenance release fixes a crashing bug and improves support for iBooks for Mac in Mavericks.
Apple's brief patch notes in full:
This update fixes a problem that may cause iTunes to quit unexpectedly when a device is connected and improves compatibility with iBooks for Mac on OS X Mavericks.
The update is an 81.4MB download through the Mac App Store. You can download a 232.7MB standalone installer through Apple's iTunes site.