I think you'd attract/retain more users if you added a way to demo the game without having to login/register (despite the fact that the registration is quick and easy), and then prompting them register after completing one or two quests.<p>In my experience, people turn away as soon as they see the a registration form if they haven't had a chance to play first (or unless the game is already very popular). Do you have any analytics running on your site to track the bounce rate?