ExtremeTech has taken a look at three motherboards: two with the new X38 chipset and one with the P35.
We'll be taking a look at a pair of high-end X38 boards from ASUS and Gigabyte. Curiously, Intel's own X38 motherboard is still in development, apparently having some teething problems, though Intel anticipates shipping its own boards in the November timeframe. Given the delay, the motherboard makers have had extra time to tune their products, and it shows, as both the ASUS and Gigabyte boards seem quite refined for first releases.
Check it out over here. The site reports these new X38 motherboards offer a lot more overclocking potential than the P35. However, if you don't plan to overclock your system it's better to buy cheaper motherboards with the G33 or P35.