The Intel X48 chipset will be faster than the X38 and is described by FUD Zilla as an overclockers dream:
Tier one the usual suspect including Asus will be among first to get them. These boards will be the top of the iceberg and they will be the best of the best, and so will the chipset.
It will be interesting to get our hands on it as X38 / X48 motherboard will leave all P35 boards sitting in the dust.