Although we've been aware of the CPU and memory Voltage issue of the Core i7 and the X58 chipset, the first official word on it all has come not from Intel, but rather Asus by the means of a sticker on the memory slots of its P6T Deluxe motherboard.
This seems to indicate that the solution to the problem wasn't as easy as it was thought to be, and separating the Voltage might either be more complicated, or it could just be that the first generation of X58 will have to live with combined Vcore and Vmem.
The sticker reads "Accord to Intel CPU SPEC, DIMMS with Voltage settings over 1.65V may damage the CPU permanently. We recomment that you install the DIMMs with the Voltage setting below 1.65V" and if that's not warning enough, we don't know what is, as frying a Core i7 won't be a fun or cheap experience.
You can find the sticker picture as well as a few more additional pictures of the P6T Deluxe motherboard here
X58 boards with separate voltage possible
Nehalem only supports DDR3 800 or 1066