I have an ipod touch. You can lock it down really well through the parental controls. I have Safari turned off, which is the basic (unmonitored) browser and I have a browser called Mobicip installed which tracks every site that is visited. You can log into their website and see what was visited on the ipod. It also blocks sites that you would want blocked by category and also any specific ones you whitelist or blacklist. But that’s only if you want internet use like that, if you don’t want it at all just block Safari and it’s gone.
Aside from internet use, you can turn off the app store if you wish, or require a password to install programs. A new feature I like sets it so you need a password to DELETE applications. Which could be good for someone who likes to install games/apps regularly but still wants the accountability. There also rating restrictions that can be enabled for both apps, music and podcasts.
I was surprised at just how much you can lock the device down if you wish to. Hope that helps!