This seems to be the current forecast for the Moon's polar craters, as it presumably has been for the last few billion years, and will continue to be for the next few billion.
Not much (only one heavily processed image) has come out officially from the L-CROSS team since their mission scored a lunar bull's eye, minus the photogenic plume that was supposed to be the media highlight of the show. But in the grand old aerospace industry tradition of using Aviation Leak to get the story out, the L-CROSS team dropped some hints in the online Sky & Telescope about what is going on behind the scenes.
The impact did produce a plume, but it was about 10 times less massive than expected. Why it was so sparse is not yet known and may never be fully known, but new hypervelocity impact modeling suggests that debris may have gone more 'out' than 'up.'
There's also mention of the Centaur booster stage 'collapsed into itself when it hit.' I am not quite sure what to make of that last part. You'd expect any tank structure to 'collapse into itself' when it slams into the Moon at 1.5 km/s. But fans of kinetic weapons, including me, take note: There is a lot that we do not know about uber-fast impacts.
As for what was in the faint plume, Sky & Telescope gives contradictory hints, noting that the IR signature of water vapor is conspicuous (and implicitly absent), but also broadly hinting that when an L-CROSS public announcement comes, in a couple of weeks, the team may reveal that it did detect water. But not, I suspect, very much of it. What they did detect, rather oddly, is mercury.
The article also has one other interesting tidbit, though not from L-CROSS. Apparently an instrument aboard the Lunar Reconnaissance Orbiter determined that the surface temperature on the floor of those permanently shadowed are only about 35 K - much lower than anticipated, and making those spots the coldest known place in the entire Solar System.
And right in our local 'hood. How cool is that?