I know that human user verification systems in blogs are there for a reason, but we really need to come up with a better plan. Here's what I got on blogger today trying to post a comment:
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That would definitely stop any robot, let alone any human!
(yes, I know that you can ask for a "new" image to be created for you, but you're losing the point of going in, leaving a quick comment and going away. It's not "casual browsing" anymore. It's a small project!)
On a related topic.. If this isn't enough, you know you should stop using word verification when Google starts using nasty words in their verification images :-)