SOMETHING needs to be done. I can't tell you how many times I have worked long and hard on a response to a question, and then posted it only to see the message that "this question has been deleted." And for people who are following Y!A guidelines, to have a question or answer or even an account deleted because of malicious reporting is not just unfair, it's going to cause people to abandon the forum, and the forum does have a legitimate value for millions of people worldwide.
On the other hand, Y!A answers was created with specific guidelines prohibiting threatening responses, verbal abuse of questioners or other respondents, obscene language, spam, and so forth. Those are the rules by which we have agreed to play, and if we are unwilling to do so, then we should find a forum more in keeping with the sort of tone we want to view and use. I have seen some responses that were posted for no other reason than for their shock value--responses that threatened to kill the questioner, questions with nothing but salacious language or gratuitous obscenity. As far as I am concerned, these sorts of questions should be reported, but many people who would like to report do not do so out of fear of retribution.
So what's the solution? Ideally, if a question abuses Yahoo guidelines, we all should report. If that were done, those who abuse would stop, and those who are doing malicious reporting would become highly visible, because they would have no support from other members.
Finally, something needs to happen on Yahoo's end of things. If someone reports maliciously, the person being reported needs to have some recourse. And if it can be shown that malicious reporting occurred, let THAT report monkey have his or her account deleted.