A Microsoft patent approved in the USA on December 30th may cover a number of key elements of the Xbox 2 architecture, including the multi-processor system which can be used to generate geometry on the fly.
The patent, which describes a "system and method for parallel execution of data generation tasks", almost certainly refers to Xbox 2 but reveals little about the actual hardware in the next-generation console.
What it does show is a system with multiple distinct processors (the actual number of CPU cores isn't given) which interface into a single graphics processor (GPU), which ties in with the expected multi-core design of the Xbox 2.
The patent, which was uncovered by US website TeamXbox, goes on to describe a system whereby the first ("host") CPU handles normal game tasks, while the other CPUs are set to work creating procedural geometry and "fine-grained processing associated with a game".
The example given of this in the patent is setting a processor to work on generating a realistic tree using geometry data for a leaf and physics data for the world around the tree - technology which would relieve much of the huge burden which generating art resources for next-generation games presents to developers.
A system such as this was described by J Allard at E3 last year, when he talked about the potential for "procedural synthesis" which would take advantage of the processing power offered by the successor to Xbox.