If you don't know what you are doing with nofollow, noindex and robots.txt you can royally mess* things up (face to face I would use a stronger term). Even if you do know what you are doing, you can still mess things up.
I can understand why Matt Cutts might want to change what noindex does, it is not just Koreans making occasional mistake, for instance I just noticed the whole WebProNews video blog is currently noindex nofollow. I am sure that is a mistake, it is easy to make in Wordpress… just one click and save.
All in one
Multiple Reasons Why I Loathe Top Commenters Plugins
I benefit from being a top commenter on a number of blogs simply because I am consistently active on those sites, and I have gained the benefit without changing my commenting habits.
Some of my blogging friends are aware of the problems, but have opted to use such a plugin anyway – I fully respect that decision, but many make that decision “blindly” without being aware of the possible consequences.
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