Uh, this better be temporary. We gush about the iPhone 4's hot new upload speeds, and AT&T takes it away. Upload speeds in several cities, like New York, are capped at 100kbps - one-tenth of what iPhone 4's capable of.
That's the reportage from MacRumors forums, and we're getting the same results - zippy downloads in New York, but upload speeds are stuck below 100 kilobits per second, a far cry from the 1500+ we were seeing a week ago. And it does appear to be regional - so far, it looks like NYC, Central Jersey, Boston, Orlando, Seattle, South Jersey/Philly, Columbus, Cleveland, West Houston, Phoenix, Northern Colorado, St. Paul/Minesota, Suffolk County/Long Island, Quad Cities, South Jersey, Denver, Detroit Metro, Cincinnati, Baltimore, Salt Lake City, Las Vegas, Kansas City, Fairfax, Minneapolis are affected.
It does appear to be a regional outage/restriction. Our tests in Chicago show the kind of upload speeds you'd expect - 1237kbps.
We've reached out to AT&T for comment, but the most likely explanation is an outage or maintenance work related to HSUPA (basically, the network protocol that allows faster upload speeds, toward the 1Mbps range) in these areas. In the meantime, there's no word on when the pipes will open back up - hopefully soon.
Update: An official comment from AT&T is incoming, supposedly.