Unless the messages themselves violate policy, we might as well keep them.
Hey, look on the bright side. They are compliments. Now let’s say that this gets out of hand, then we can start reverting/blocking.
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These often happen a day before we are visited by the more familiar spambots that post their nonsense links, but it has been four months since the last real wave a spambot posts, and I have never seen a ‘‘flood’’ prior to these previous events. They are harmless as they are, so it would seem counterproductive to revert them or to react to them for the time being.
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It is beginning to appear that these random posts may be preceding a round of spambot posts, here is another one that was posted this morning, after a similar discussionpage post earlier http://www.wikihow.com/index.php?title=Discussion:Create-Dice-Nail-Art&diff=prev&oldid=8970477
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Hm… Interesting! I just ran check user on each of the IP’s behind those edits. They are single edits only, no other users or edits from that IP. It will be nice to have these links available so we can see if they are the source of other spam in the future. Feel free to ping my talk page or email with these if they start getting out of hand, but for now, every link above this message was one of this nature… no other edits, no other users from that IP, so if you see it come up again, you know you can block it safely.
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I haven’t looked at the block log, but in the past, the proxy blocker would be blocking many ISPs when these posts begin to appear, so it has been safe to assume that these bots are using proxies, and so they all appear to be unique ISPs even if they are not. I am not sure, however, if the proxy blocker is even still in use?
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Possibly? but I’m not knowledgeable on how the proxy blocker works. I’ve seen blocks with the notation “blocked because this IP is an open proxy” as recently as this past week though, so I would assume the proxy blocker is still in use.