I have been recently searching for a good screenplay review organization to join in which members can share their "work-in-progress" script and receive constructive critizism. As of current, I haven't found the right group.

If I were to create an online organization for this, would there be any interest?

If so, email me at nicholas@rule-42.com.

There is although one existing already: www.celtx.com. They offer you free scriptwriting software and chance to get reviewed by other authors.