Just out of curiosity, how many of you people that are still having this problem have tried resetting their network settings as suggested by another user in this thread? (Go to GENERAL settings, scroll to the bottom, click on RESET, then select "Reset Network Settings")
Other than shutting down Skype after use, and turning off "Location Services"and "Bluetooth", the only other thing I did was to RESET my network settings, and since I did, I am NO LONGER having this problem with my iPod Touch 4G!
Give it a try people. I easily get a week of standby time out of my Touch 4g, and when used continuously, it lasts more than twice as long as the 2g did. (PS: setting the screen brightness to 50% helps a LOT to extend your time while you are using it... I get about 5 hours of continuous use before it needs a recharge)
One last thing, on a recent 18 hour flight, I was able to keep my iPod working almost all the way through using this handy little portable recharger from Duracell that I bought on Amazon for $25:
*Duracell Instant USB Charger with Lithium ion battery*
http://amzn.com/B002FU6KF2
This device allowed me to charge my iPod Touch 4g from a completely discharged state to a 70%-90% SOC in about 30-45 minutes!