@jerrydaniels yeah. iOS 4 had it. If you touched on the blue arrow next to the network you were connected to it pulled all particulars including a button at the bottom that said 'forget this network' forcing your device to go back to 3G. iOS 5 doesn't have the same button. Good for coffee shops where the Wi-Fi is bogged down from heavy traffic and you want to jump over on 3G to speed things up. :)
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