Anandtech has an article showing which mobos are Kentsfield compatible.
Now, mind you, that these results were from the manufactuers and weren't really tested by Anandtech, and we all know the hassle when Core 2 was first released and how many "Conroe Compatible" motherboards weren't. But if this list is true, then the 975x chipset based boards are not the only ones that should be able to use Kentsfield, but also the 965 chipsets.
Here's the link: Kentsfield compatible motherboard listing
Now, mind you, that these results were from the manufactuers and weren't really tested by Anandtech, and we all know the hassle when Core 2 was first released and how many "Conroe Compatible" motherboards weren't. But if this list is true, then the 975x chipset based boards are not the only ones that should be able to use Kentsfield, but also the 965 chipsets.
Here's the link: Kentsfield compatible motherboard listing