As several folks have already noticed and taken advantage of, you can now leave comments on FLOG. You must be logged in to leave comments, so if you're not registered yet, why not do it right now?
The commenting process itself is fairly self-explanatory. If there's a particularly hot discussion that you want to follow, or if you want to know if anyone responds to your trenchant observation, the comment thread of each and every FLOG post has its very own RSS feed — the link is right at the top of the Comments section.
At this point we don't have any hard and fast rules about acceptable commenting etiquette, but we do reserve the right to remove comments at our own discretion and block any egregious repeat offenders. Comments of a commercial nature promoting artists and products not affiliated with Fantagraphics will, for the most part, not be tolerated and be treated as spam. That said, we're all pals here, so let's play nice!