This program modifies the HWPSTATE tables in the model-specific registers, just like k10ctl. The nice thing about this interface is that P-state transitions are not managed by software, but done completely in hardware. This is much more robust than CnQ on the K8 and the implementation in the OS is a lot simpler (basically, the driver merely provides hints to the CPU which P-state it wants to switch to). It also makes stuff like the turbo mode possible, by overriding the software hint.
Yeah, that's good if you have a K10. I thought this new program would fix that but it seems that K8L is a very small subset of the K8 family. Too bad. :)