Back in my university-years, I spent many extra-curricula hours debating the existence of God over beer and pizza. I thought the issue was all sorted, but judging by the BigThink fourm, apparently not. The subscriber-base seems equally divided between the godders and the non-godders, leading to lots of related traffic. While all forms of mental-exercise can be worthwhile, there could be the danger that overemphasis on this topic could create a background-buzz that totally obscures any sign of intelligent thoughts and comments on other equally-worthy topics.
This leads to another thought... The rate of adding ideas has increased dramatically, but there is also a corresponding rise in the rate of repetition. Theoretically, idea-growth should be slowed by contributors having to research ideas already in place, before adding their own. There is evidence that this may not be happening, with members sometimes taking the short-cut and posting blindly, regardless of the quality or originality of the idea. If BigThink is to maintain a high-standard, this practice should be discouraged.
The effort in an idea is not the having of it, but rather the research required to determine its value [ could that be another quotable-quote? ].