Wow, thanks guys for the information. One quick thing:
I decided to ask some "online AT&T live rep" regarding this and she was saying complete nonsense. Chat:
ME: I have an unlimited data plan with my iPhone 3GS. If I were to ever purchase a new phone such as a new version of the iPhone or an Android phone without signing a new 2-year agreement, could I still keep my unlimited data plan?
REP: If you don't sign a contract the Unlimited Data Plan won't be offered.
ME: So if I purchase an unlocked phone and try to use data on it (ie. web browsing) what happens?
REP: If you're purchasing a Device through someone else other than AT&T you won't be able to keep you Data Plan.
ME: So the data plan disappears from my account? I'm confused.
REP: Correct Unlimited Data is no longer offered, if you're not Upgrading with a contract, you can't keep the Unlimited Data.
REP: The DataPlus plan is $15 per month for 200MB of data. This plan is designed for people who primarily surf the Web, send email, and use social networking apps. The overage charge is $15 for another 200MB.
REP: The DataPro plan is $25 per month for 2GB of data (10x as much data as the DataPlus plan). This plan is designed for people who regularly download or stream music and video, or use other high-bandwidth applications. The overage charge is $10 for another 1GB.
ME: Right but if I don't sign up for those plans and just purchase a new phone how exactly would those apply?
ME: I'm asking if I purchase a new phone and don't change my cell-phone plan, why exactly would my plan get changed?
REP: This is the way the system is arranged, and being that Unlimited Data is no longer offered this is not an option in the system.
ME: I see. However, it appears that your own website (AT&T Support Forums) says otherwise
REP: I understand! If you do see where you are able to keep Unlimited Data without Upgrading with a Device from AT&T directly, then you will be able to keep this Plan.
REP: If you purchase a new Device as I mentioned before you can keep your Data Feature as Unlimited.
ME: This is a direct contraction to what you mentioned earlier.
REP: I'm sorry if you read our conversation, I did tell you this exact information.
REP: I'm sorry if you misunderstood me, but I have researched this Chat also and above this information is mentioned to you.
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