According to a post provided by Gameranx on Dec. 2, a hacker by the name of Hector Martin seems to have given information regarding the CPU that will be implemented into the next generation Xbox, or Xbox 720. As with any type of speculation or rumor such as this, fans should take this with a grain of salt, as the following information has not been confirmed by an official source. Nonetheless, you can take a look below to see the information that was provided through Hector Martin, in regards to the CPU that the Xbox 720 will be supplied with.
If you want more evidence that MHz isn't everything, a little birdie points out that Durango (Xbox 720) is specc'ed to have a 1.6GHz CPU.
Food for thought. (And don't bother asking me who that little birdie is.)
Through the information given, Martin compares the processor of that the Xbox 720 will supposedly be shipped with, to the CPU that is provided with the recently released Wii U. The Wii U's CPU is clocked at 1.2GHz, while the rumored CPU for the Xbox 720 will be clocked at 1.6GHz.
Fans should realize that these numbers mean absolutely nothing without information regarding the way that the processor is set up. Overhaul clocks is not representative of the power within a CPU, is the way the CPU architecture is structured.
Additionally, fans may also be interested in the slide-show listed above this article, which is comprised of unofficial concept photos of the Xbox 720.