Don't know. here is the next "Duron" which is called ther Thorton. Basically it is a Barton with half the ondie memory. Kinda stoked up about these! Hope they hit the market.
http://www.hexus.net/
I bet all the Hammers/Opterons will have these IHS though. Already trying to figure a way to Direct IHS water cool it. There might be enough room on the Opteron IHS to seal it on the IHS itself. Hard to tell though without a scaled pic.