I'm just throwing this out there, but...
I moderate two forums. Reports from both forums go straight to a junk mail folder that gets cleared out... well, whenever. I never, ever go into that folder.
HOWEVER... Whenever I am online, I get little pop-ups saying that someone has reported a post - because I get that e-mail alert. When that happens, I usually swing back by the forums ASAP and delete any active SPAM. So, personally, I favor a quick report of the SPAM, but that's just me.