I am using IOS 6.0.1
Go to SETTINGS.
Then to GENERAL.
Then to RESET.
Then to RESET ALL SETTINGS. (This doesn't erase pictures, music, and apps. It just resets the settings. It does reset privacy settings also.)
My IPod Touch is zipping along now.
I believe that IOS 6.0.1s new PRIVACY settings features were slowing down my iPod. Could be several things, but now it feels fresh.
If you had set any alarms, you have to reset them. If this guide does not work out for you, check out the FIX A SLOW IPHONE guide by AMANDA MAX.
It has been brought to my attention that this erases wifi passwords. Only use this guide as a last resort, until I explore exactly what settings are changed. Apps and Content are NOT erased though.
Update: Only the ERASE ALL CONTENT AND SETTINGS will delete email accounts, but RESET ALL SETTINGS makes your iPhone like new, without deleting content.