This information was released to MINI dealers in the form of an “Aftersales business development & marketing MINI dealer bulletin”. It comes via Ian Cull:

jcw

Based on requests from MINI dealers, please find enclosed information about the John Cooper Works Tuning Kit for the MINI Cooper. We have a limited number of this kit available in the US.

The JCW kit is a complete performance package that is designed to take full advantage of the engine's design. The JCW Kit for the MINI Cooper includes a machined cylinder head for better airflow, “cat-back” exhaust system, air filter element and updated ECU programming. These carefully engineered performance modifications will bring the MINI Cooper to the 126hp horsepower level. The torque has been improved to 114 lbft.

As the kit delivers only a minor increase in horsepower and torque, the main benefit is the increased performance feel and mid range torque of the MINI Cooper.

NOTE: This kit is only available for the manual transmission MINI Cooper! It must not be installed on cars with optional automatic gearbox.

Wow. Ian reports seeing a price of $2650 plus labor and I can now officially confirm that price. The kit is currently available is already on back order throughout the US!