There's a story over @ TheInquirer.net that could explain why Intel have got their knickers in a twist. Well back in 1999 AMD had a brain wave and filed a patent at the US trademark and patent office numbered 5,944,816, entitled "Microprocessor configured to execute multiple threads including interrupt service routines", outlines how a CPU can execute multiple threads concurrently. So this gives them the rights to release a processor with hyper-threading technology and maybe a Rambus style law suit.