No need to get your panties in a wad. I was talking about the 16 and 32GB models, but I should have been more specific. The 8GB model was actually released after the 16 and 32GB were discontinued. Apple did keep the 8GB models around longer than most of its other models (as a "free" option for people buying phones on contract). From a hardware perspective, those are completely different models.
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I believe Facetime video only works over WiFi for the iPhone 4, while it works over cellular with more recent models. I could very well be wrong though. It really doesn't matter though. There are plenty of other examples. My point was that technology companies can only go back so far when adding new software features to their product line.