According to a tweet, the CPU is not based on IBM's Power 7 chip, as previously believed, but rather a Power-based CPU.
Nintendo has been taking some heat for an apparently sluggish processor in its Wii U console. There has been some speculation before that Espresso may be just an updated version of the Power-based Broadway processor in the Wii, which is a 729 MHz chip manufactured by IBM in a 90 nm process. Some developers have complained that the new processor does not have the necessary performance to run games at a similar level as the Xbox 360 or PS3.
Nintendo previously announced that the WiiU will launch on November 18 for $300 (8 GB, white) and $350 (black, 32 GB).