Delete iTunes temporary files in CCleaner.
There are well over 100 million Apple devices that use iTunes according to Apple. I'd guess that more than a few of those people also enjoy keeping their system tidy with CCleaner like myself. It may be a market to consider - cleaning iTunes automatically without using the manual method above, which is not comfortable for many users. CCleaner can also use its great 'Delete older than 24 hour option' here.
Google searches show lots of people complaining about GB's of temporary files.
Locations of log files (mostly sync) with iTunes in Windows 7:
C:\Users\<username>\AppData\Roaming\Apple Computer\Logs\*.log
C:\Users\<username>\AppData\Roaming\Apple Computer\iTunes\iPhone Updater Logs\*.log
C:\Users\<username>\AppData\Roaming\Apple Computer\<username>\CrashReporter\MobileDevice\<old crash reports>
In addition to the temporary iTunes conversion files throughout:
C:\Users\<username>\(My )Music\iTunes
If there are errors or iTunes is having problems with plug-ins, then it appears to stop cleaning the temporary files on its own.
Thank you for your consideration!