From the site:
Writertopia provides a few tools for the writing community. It’s a way for our team to play with new web technologies like Google’s App Engine, and see if our experiments are useful to writers.
Writertopia is focused on our members’ professional development. We will actively recruit writers who are trying to hone their abilities and receive feedback on their work. We want our best members to invite others who will help build a collaborative, skilled community. Initially, we are limiting the number of members until we feel the website can be scaled in a cost-effective manner.