The term Freshies can be applied in many different situations. I would agree first and foremost that it relates to fresh snow/powder, but it can also be used to describe something new, or a great looking chick (doesn't work for describing a guy).
A very versatile word. See below:
Used when snowboarding: "Check out the freshies on the freshies over there!" - this could mean: Check out the new clothes on the hot chicks over there (who happen to be boarding on the freshies) or it could mean: Check out the hot chicks boarding on the fresh powder over there.