In the forum http://forums.finehomebuilding.com/breaktime/ (same forum that was one of the subjects of this thread) we're seeing a lot of "spam" of a curious sort. Obvious non-native-English speakers make posts that are vaguely on topic but seem pointless. Eg, this one:
Installation of vapor barrier depends upon the climatic conditions where you live. when moisture passes from the wall it can cause mol and mildew on the walls. Vapor barrier insulation can be installed towards the living space.
These people will drop in, make a handful of posts, and then disappear. (Though occasionally, if called "spammers", they will vehemently object.) And the posts no doubt take some time and research to compose -- it's not a bot.
Any idea what they're trying to accomplish (other than annoy us)? About the only thing I can think of is that it's a game (or maybe even class assignment) for English students to see if they'll be "outed". Or perhaps training for soon-to-be-spammers who aren't yet allowed to use links.
(I suppose some might think that such posts will "trick" the spam blocker into accepting the user, but, honestly, the Mollom spam blocking software is so crummy that this isn't necessary.)
Here is another example, in response to a brief query about (construction) project management software:
Using a software will always streamline your work. It is nicer to having your systems in palce so that you do not waste too much time with a pen and a paper and organizing and managing your work. It is important to go through the reviews of the softwares before shortlisting. Also it is required that you take a demo of each and see what suits your needs and organization the most. Be sure of the trining and service of the software providers.