THere's an embargo till december 2009 of the SELENE science results...But Ciel et Espace has given some interesting hints.

Ice inside Shackleton?

Problem: same radar echoes from inside the crater as its sunlit surroundings. It could be a particular land texture.
Kaguya has been able to catch photons from the area in permanent shade and there appears to be a nippled relief there, which can explain the radar signature (and might make walking there kind of tricky, shadow notwithstanding).

Kaguya has 2 mini-satellites, Okina and Ouna, and are used as relay transmissions to the Earth while Kaguya is orbiting farside (even Apollo couldn't do that)...and theres a decrease of gravity on farside (while nearside has mascons which increase gravity, it's the opposite on farside)! The width of the crust on farside is such (100 km) that the big impacts have not affected the mantel in a way that would have allowed denser rocks to resurface. Porous Brecchias dominate farside and reduce gravity.