This has been reported on numerous forums. With the latest iOS update, the indicator now shows 4G when in an HSPA/HSDPA coverage area. Those are not true 4G networks and you are not getting LTE on your phone. Based on the release of the new iPad later this week, every indication is that the next iPhone will support LTE data, but not with any current iPhone.
Today when my home WiFi was accidentally unplugged, I turned my 4S on and it showed 4G. This is the first time it has shown that, all the rest was 3G.
I don't live in a city with LTE so I'm wondering if 4G is the new 3G for ATT and what difference it makes if any.
Thanks...

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