The Catholic Caucuses are posted mostly late at night whereas the LDS Devotionals are posted during the day. And currently the "everything" browse intermingles Religion Forum posts with News/Activism.
Therefore we have been getting many, many News/Activism posters - even oldtimers - wandering onto the Religion Forum shocked and complaining that the site is overrun by Mormons. That of course is not true.
In terms of "open" thread heat v light ratio, the ex-[pick a confession] threads burn the hottest. But in terms of longevity, the Catholic v. Protestant debate (by definition) will never end.
You can always find heated intra-Protestant debates by looking for threads about dispensationalism and end times prophesy.
I've noticed that since the "redesign" a couple months ago. Someone wanders onto a thread that is actually fairly tame and seems shocked at the tone of the debate.