So yes, blacklists are mostly not an issue. Mostly. Because there is one way to get on a blacklist. That way is to behave so appallingly badly in public that every editor in your genre decides independently that they do not want to have anything to do with you ever again, in case they have to deal with the crazy. Editors do not like having to deal with the crazy. They can always find another author who doesn't do what Kevin W. Reardon aka Cole Adams appears to have done, which is to repeatedly suggest to an editor suffering from depression that he should commit suicide, and follow that up with a death threat. All because said editor had a one line unfavourable comment about Reardon's short story in a post commenting about stories he was considering for a reprint anthology.
Poppy Z Brite has a particularly lucid summary of what happened at http://docbrite.livejournal.com/656
I did the odd bit of anthology editing long and long ago. The therapy worked and I'm on the wagon, but I can still see things from the editor's side of the slushpile, if I squint. This is the sort of thing that makes me think that the easiest way to deal with seeing a particular name at the top of a submission is to reject it without reading it. Because who wants to deal with edits on a story where the author is that sensitive to any suggestion that his prose is less than perfect?
[*The editor in question confirms that there's solid evidence it's really Reardon in a comment to this post: "Please note that I asked the publisher of the anthology to speak to the author. He did so and received word back, confirming this was not a case of 'sock-puppetry.'" ]