50,000 users? Proof?
Right now its just a very vocal minority. 50,000 iphone users roughly equals 5 million dollars in revenue, which, if this was a legitimate issue, would be 5 million dollars in lost revenue. ATT Mobility (wireless) made 10.5 Billion dollars in just DATA services revenue in FY08, and on top of that, sold like what 20 million iPhone 3g's also in 08 (but I can't get a firm number, someone correct me if they find a figure).
"50 thousand" users accounts for about 1/400 of sold 3g's. 5 million accounts for 1/2100 of the overall revenue from data.
Considering these users probably won't jump ship, I'd say ATT has better things to worry about.
I'm speculating here... Not everyone who is upset by this is a twitter user. In fact I think it is safe to say that the majority of iPhone owners upset by this don't twitter.
This is a simple short term vs. long term situation for At&t. Me personally, because of the extra charge I will not upgrade. At the end of my term I will then decide what the best phone is for me... it could be an iPhone or it could be something else. One thing is for sure though, I wouldn't have to make that decision if I were to upgrade to the 3Gs now... I wouldn't want to pay an early termination fee and therefore At&t is guaranteed me as a customer beyond next year.