In my five years of BLOG writing I have had to deal with a few BLOG trolls, SPAMMERS, or just someone providing an overall negative comment. I call them the "Negators" and typically I recommend just deleting their comment and not letting it obther you.
From time to time, I've been known to not take my own advice and respond to the "Negator" by properly educating them and, as politely as possible, put them in their place. This rarely ever turns out in a positive light as many people have BLOG or email "guts" and with their ignorance and negativity can still make you to look out to be an unjust perpetrator.
All in all, just ignore their comments and empty threats and move on to something productive and lucrative and feel better knowing that you are a better person than they are.
Remember - Never argue with an idiot ... they will beat you with experience and those witnessing can't tell who the idiot is.