AT&T user here. I was more pissed off about these limits until I started using an app that shows me my data usage during the month and I had a surprising result: I only use 200 MB a month!! I thought I was someone who would be near the 2GB cap I have, but I am quite wrong.
During my afternoon commute (~2 hours) on Amrtrak I use my phone to Facebook (including a lot of picture uploading), Twitter, web browsing, e-mail, light gaming and app downloads & usage. All of this is on 3G (or "4G" if I am to believe AT&T's marketing speak that HSPA+ is 4G). Weekends out around town is the same profile, though evenings and such at home I am on Wi-Fi. So to be using only 200MB was a shock to me.
All I am saying is that we should all look at our usage before we are outraged. Yes: it is RIDICULOUS that they market "unlimited" data when throttling is, by any reasonable definition, limiting. But how many of you are really at or near the caps? I would really like to know!! I wonder how many of you are like me, thinking you use more data than you do.