AMD's OverDrive application is something that AMD is going to pit against the well accepted Ntunes from Nvidia. AMD went one step further, as it can overclock each core individually. Neither Nvidia nor Intel can do this today and Intel will have to do some serious catching up to make its own Windows-based overclocking tool.
This tool works with the RD790 motherboards that will also launch in some 10 days and we know it won't completely support Nforce-based motherbords, at least not to start with. It will work on Nforce boards but you won't be able to overclock, etc.
If you end up with a 2.6GHz Phenom you will be able to overclock the first two cores to 3.0GHz, while the rest of the CPU can keep working at 2.6GHz, at least in theory. It will be very interesting to see how this thing works in the end.
The tool works under both XP and Vista, which is a nice change.