However, we've got a new feature that I'm hoping will (eventually) play a significant role in changing how people use LessWrong: sharing drafts.
When you create a new post, you can now share it with specific users. And then, if you submit it as a draft, they can view it even though it's not posted publicly. (They can also comment on it. It's up to you whether you want to encourage this for a given post)
Currently there are no notifications associated with this, and will probably be awhile before we build out additional features one might want for this (easily sharing with groups, in-line comments, allowing multiple users to edit, version control, etc). But I wanted to at least get this basic feature out sooner rather than later, and am hoping for the longterm for this to be part of the move towards a more peer-review-esque world.
Right now LessWrong sort of encourages you to come up with an idea, write it up, post it, and then maybe there are comments and critiques but you don't actually go back to rework the original post.
Longterm I'm excited by the prospect of "write the post" just being the beginning, and having various formal and informal systems for having improve that post being a continuous, important part of the process.