The MacRumors forums are abuzz with users comparing their recent upload speeds. TUAW reader Becca Holmes tipped us that iPhone users are experiencing uploads that appear to be capped at 100 kbps rather than the 1.6mbps that was a previous norm. Users have been comparing rates captured with tools like Speedtest.net's Speed Test to put concrete numbers on perceived performance drops -- and it looks like that drop is huge, compared to the way things were just a week or two ago.
According to the thread, affected cities include: NYC, Central Jersey, Boston, Orlando, Seattle, South Jersey/Philly, Columbus, Cleveland, West Houston, Phoenix, Northern Colorado, St. Paul/Minnesota, Suffolk County/Long Island, Quad Cities, South Jersey, Denver, Detroit Metro, and Cincinnati. Upload speeds affect your ability to send picture- and video-email over 3G, as well as to upload any kind of bandwidth-hungry data using your 3G connection.
TUAW gave the test a spin in Denver, using SpeedTest.net's application as well as FCC Mobile Broadband Test and iNetQCheck. We experienced similar numbers as the ones reported in the MacRumors forum, with several stray data points in iNetQCheck runs -- but even those remained below 200 kbps. That's a huge difference from the upload speeds reported just a week or two ago over at AppleInsider. Compare the SpeedTest.net results on the AppleInsider write-up to these. AI demonstrated upload speeds up to 3.5 mbps. Using SpeedTest.net, we never cracked 100kbps using 3G.
So why the sudden change? We have contacted AT&T for a statement but have yet to hear back from them due to the holiday. Our guess is that this comes in line with AT&T's recent data plan changes, in an attempt to enforce data austerity and guard AT&T's business from high bandwidth demands from data-intense devices like Apple's iPhone line. Update: Some commenters (and former enterprise engineering type Steve Sande) suggest that the hypothetical upload caps may be a consequence of holiday weekend infrastructure work, and that speeds may return to normal tomorrow; we'll check.