May have found a fix to battery discharging
After many days of trying a few posted options to get my devices to stop discharging, I isolated the issue.
The problem began when I switched routers and updated from a g to an N router. The positive effect was immediate. Greater reception, faster download times... blah blah blah but, suddenly, all the Itouch(s) in the house where discharging overnight.
It coincided with an OS upgrade and additional apps download. Naturally, I turned to the Itouch itself.
Having tried everything from turning off notifications, hard reset, deleting apps, dumping the network, resetting 3 times, going to static address... etc, nothing worked.
I finally had an epiphany, turned off all the devices, reset the router (turn off or unplug for 1-3minutes) and voila, it's no longer a problem. It works.
The router as it turns out, was broacasting a weak signal every once in a while (happened twice in a month) that was competing with other signals in my network. Naturally, that forced the Itouch to "hunt" for a better signal in the vicinity (wireless roaming) to acquire. Problem is, it eventually finds the weak signal and requires it, having gone to a reboot of sort to generate the password and everything else from memory.
Initially, it can be difficult to detect because all the other wireless devices are still functional (laptop, Ipad) and are not being affected.
That excercise is repeated, almost like a loop several times. The Itouch loses the signal and reacquires it, quickly. If you go settings>wifi>choose a network> IP Address, you can see the address dropping off and being reacquired. Incidentally, this doesn't matter whether you are in DHCP or Static mode because the culprit is the wireless router/modem, not the Itouch.
If you've ran out of options and you find yourself in this dilema, don't forget to reset your wireless router as well as trying other options mentioned here and elsewhere.
Hope this was helpful.