Core 2 Duo clearly superior to AMD:
Intel is back and dominating AMD in processor war. However, don't count AMD out just yet. They have plans. Core 2 Duo give Intel a clear performance advantage over AMD for the first time in years. AMD introduced aggressive price cuts while mainstreaming chips like the Athlon X2's to riduculous low pricing. Later this year, AMD will launch 4x4 which enables systems to use a pair of high end dual core chips. This will be expensive though. Further in the future, AMD will open it's HyperTransport bus to allow other companies to design specialized co-processors and accelerators to be used with it's high speed HyperTransport bus.
AMD's true answer to Intel's Core 2 Duo will come next year (2007), when they expect to launch it's next generation K8L architecture, including single quad core CPUs.
However, Intel has also something up it's sleeves as they claim to have discovered a way to reduce or eliminate electron leak in modern day CPUs which will in turn, significantly boost performance. Read here for more info about this. Pretty interesting stuff:
http://www.newscientist.com/article.ns?id=dn4351