True. Though they usually want it to be in a different form or not completely online. First three chapters versus the entire work will sway them more, but they also can get an idea of how well received it is (if they bother to check). If you are in it for the money and to be picked up by a non-POD publisher, I would seriously reconsider sharing that work on YWS.
Though if you do something like Lulu, you shouldn't worry.
