AT&T capping upload speeds for iPhone 4 users?

A lengthy thread on Mac Rumors’ forums dating back to July 4 suggests that AT&T is at best experiencing data difficulties and at worst outright capping uploads speeds of iPhone 4 users. Many users report seeing upload speeds around 100kbps in places where they previously saw speeds of 1.0mbps and higher just a few days earlier. The phenomenon appears to be most common in major metropolitan areas, including, according to the thread, New York City, Denver, Seattle, Las Vegas, Kansas City, Washington D.C., Salt Lake City, Columbus, and Orlando. One iLounge editor living in the Orlando area has yet to see the problem in testing using the free speedtest.net app; Mac Rumors says that a couple of users have spoken with AT&T and were told that the company is experiencing data issues in much of the country, although no timetable was given for when the problem might be fixed.