Wifi bars, but no Internet connection.

After two weeks of using the new Ipod Touch 4g, the wifi suddenly stopped connecting to the internet. All other computers and my xbox has working internet except my Ipod Touch. It says that the Ipod is connected to my network and shows bars, but when I try to access Youtube, Safari, or any other application that requires an internet connection, it says that there is no connection to the internet. Both Wifi and Bluetooth addresses appear in the About section under General in Settings also.

I've tried the first three suggestions in

http://support.apple.com/kb/TS1559

, which includes reseting Networks, data, and the whole Ipod itself.
Any suggestions on what should I do?