I have the unlimited data plan, so when I upgraded to an Iphone I never paid much attention to what was considered data...It didn't really matter because I had unlimited data plan. But now with the data throttling warning, I'm trying to find out what is considered data? Is it text messages, listening to the Ipod feature on my phone, using the map function, checking facebook, checking scores on ESPN, checking my email, using Netflix, reading I-Books? Does it count against you if you're on wi-fi? I don't really understand it and I keep getting different answers from different ATT reps who just try to get me to upgrade my data plan. Is there a way to help lower the data usage without not using the phone? I checked my data online and it seems that i get large data against me at night when i'm at home on the wifi. Any help/explanations are greatly appreciated.