1. Werent you getting an FX55 (which has neither)
2. Unless im mistaken theres no such thing as Extreme Hyperthreading. Perhaps you mean the Pentium4 Extreme Edition which also had Hypethreading?
Well its just a P4ExtremeEdition which is based on the P4C (which has hyperthreading) and has an extra 2MB of L3 cache. As for HyperThreading, http://www.intel.com/technology/hyperthread/