We don't have that ability right now, but if you know code, it's very easy to add a few lines using JFBConnect to post something to a user's wall. If interested, we can tell you how to do it, but you'd need to know a bit how Projectfork works under the hood, and we wouldn't be able to help much there.
We're always looking for feedback and new suggestions for additions, and we've taken note of this one.
Thanks!