@littlecannon. Thanks. The rounded outcrops are, as you probably guessed, just spheres with displacements and texturing (specifically, Goms excellent micro-cracked .tgc)
@TU - The render time is actually surprisingly reasonable. This final one took just over 7 hours on quite a slow processor (Pentium Dual E2180 2 Ghz) with the following settings:
Detail 0.7, AA10, GI 1/3, GI blur 8, SS on. Detail jittering is on. There is one cheat though - Ray traced shadows are OFF. The reason for this is I was having big problems with patches of blackness on the terrain, perhaps due to missing data (it's a DEM). I can get away with it because the sun is almost vertical, so the foliage and rocks don't cast visible shadows on the terrain.
Clouds and atmo settings are reasonably high; Atmo at 128, Clouds at 266. If you want, I could send a stripped down .tgd of the clouds and atmo with the final render. Unfortunately can't post it here, as it's based on Frank's Cumulus Humilis from the pack.
