I asked this question in the spring when I started Liver Cleanses also. I never got a reply, but I am pretty convinced that my little green balls were liver stones . The harder ones come out after you have been flushing for awhile.
On a side note, it's COLD, COLD, COLD in the Chicago Loop where I work and walk 1.5 miles each way to get to my office. I'm doing a liver cleanse tomorrow and I can only hope that my body retains some of that oil. I have lizard skin from the cold wind and am about to go jump into a bathtub of olive oil! My skin is so dry it hurts. Whine, cheese, whine...