Not much of a difference, but for any reasons not to make V3 and V4 compatible with any existing figure, the trend should have been an increase.

The trend of increasing polygon count is a moot point, because Poser 5 and later have polygon smoothing. Increasing the poly count of a figure puts more burden on your CPU, which is especially detrimental for animators.

If anything, REDUCING polygon count by building efficient models is the way to go. The G2 figures are very polygon heavy ... whereas newer figures like V4 and Apollo make their reduced polygons go much farther.

MORE polygons does not necessarily make a figure better.