You are not alone who has been taken granted for being a loyal customer. I have been with att since 2006 and I have had enough share of complaints and thier attitude towards my concern. I am just waiting for my contract to end, therefore I can migrate to T-mobile or Verizon.
My main complain is that - customer service reps, don't document what they inform us. I was on grandfathered plan of 550 minutes + one line on data plan with free night and weekends. However, when I wanted to add unlimited text, the customer rep, mentioned that I can change it to mobile share plan with unlimited talk and text and it would cost me only $30 more. She also told me that I can revert back to my old plan within 6 months. After trying the plan for 3 months, I decided to go back to my old plan. The customer rep with whom I spoke mentioned that I cannot revert back to my old plan as its been more than one month. When I mentioned that I was given 6 months, he mentioned that its wrong information and I shouldn't have believed it. So, currently I am stuck with the stupidest plan and waiting for the contract to be over.
All, att is concerened is getting your money, no matter what. Seems like they are also out of ideas and copy thier cell phone plans. In case, they make change in clause and give the opt out option, I will be first one.