Like most blades, HP's new BL495c G5 server blades have two processor sockets. Unlike most blades, they have two integrated 10GbE NICs, 16 DIMM slots for a max of 128GB of RAM, and two solid state drive bays. You can fit 8 of these things in 6U, or 16 of them in 10U. With dual quad-core processors, that could give you 128 cores and 2TB RAM in a 10U space!
More information is available in an InternetWeek article from Friday.