They also suffer from a technical problem - one they share with DU - that ensures they could never become a serious threat to FR even if they did start getting any posters. That problem is that their software generates web pages by creating ever-more-nested <TABLE>s for every new comment posted to a thread. This isn't a big deal for a thread that has four or five comments on it, but if it becomes popular and starts getting dozens of responses, so many tables end up getting created that it overloads most web browsers except on the most state-of-the-art, 2-GHz Pentium 4s. I open a long thread on DU and it sometimes takes as long as EIGHT MINUTES before the browser finishes rendering the page. Such "features" guarantee their forums will never have heavy participation levels, no matter what. Plenty of usability studies have shown that the average user will not wait more than seven seconds for at least some readable material to show up on-screen. If it doesn't, they move on to another site.
Making FR's threads table-free is probably the single smartest move JohnRob ever made when it comes to contributing to the success of FR. (Second was cutting threads into 50-post chunks for similar browser-overload reasons.)
Liberty Forum has no intention of being a "serious threat" to FR in any way. Good grief - read JD's post to the LF membership above.