I have to put myself on the list as well - was on vacation for a few days and since my return no luck with torrent downloading (openbittorrent, istole.it, publicbt, demonii) on multiple US servers. Was working perfectly before. I have to specify though downloads do start at one - after a long wait - point in Transmission with DHT and PEX but not so on my Mediacenter which has a built in torrent client where I don't have controll over DHT and PEX.
Is there anything we can do to get this working again?
try servers in Canada, the likelihood that trackers administrators block them is significantly lower than it is with USA servers.