A Different Kind of Comment Spam
I've noticed a slightly different type of blog comment spam over the last couple of weeks.
Whereas before you had the "classic" drugs and sex related junk or the overt "Visit my site" rubbish, there is now a new type of comment spam. They seem to be more topic based, but their comments are equally as useless as the other spammers.
For example I posted some time ago about mod_rewrite and SEO techniques. I got what looked like a "pingback" from another blog. The other blog made zero reference to my post either directly or indirectly, but had pinged me anyway.
In other instances the other blog is on a specialised subject, but rather than actually say anything of merit they are merely trying to get their link into the comments..
Quite annoying really
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Not comment spam but similar: My Wiki was spammed recently in a relatively clever way, in that the spammer posted the junk using an inbuilt Mediawiki CSS tag that hides elements (with visibility:hidden). Obviously done to build PageRank, had to delete and then lock the page to get rid of it; even then it might still be spidered by Google because of MediaWiki's History feature. Snaky bastards, pardon my Klatchian.
(To see it, go to beecher.org/wiki > Community Portal > History, pick the edit with the IP address, and then click Edit. Ditto Help:Contents.)