Is this how spammers work?

After a couple of recent posts in old threads, I was wondering whether spammers work in a different way to what I initially assumed.

I was assuming that they made spam posts, hoping they would stay on the site long enough to be viewed by forum visitors before being deleted.

But now I am wondering if the real intention is for the post to last long enough to be indexed by search engines, such as Google. I notice from a recent test that a post made only three hours ago was already indexed. So the post only has to last a couple of hours.

Once indexed, and if the site is well-regarded by Google (ie. pages in general from it will be given a good page score), then a post about some spam product may then, for days or weeks even, by "alive" on Google, and quite prominent, because of the site's reputation.

Would this be a correct assumption?

You are correct. One common method to gain link credit on Google is to simply throw your URL into a signature and make posts on forums with the hopes that it gets indexed and people click it.

However, Google is pretty smart with their indexing. My guess is that Google figures out what sites are forums and handles the links accordingly.

Still, if you want to thwart their attempts you could modify the forum software to make all links included in posts have the nofollow relation attribute (http://en.wikipedia.org/wiki/Nofollow). This way, even if Google indexes their post, their site will not get the credit from your site. It would also be extremely easy for you to implement.

This site is already pretty immune to that sort of attack, because posts cannot imbed URL tags. Only certain URLs (ones that link internally to this site) are converted automatically into links, the rest you have to manually copy and paste.

Since they are not links anyway, there is no need to make them Nofollow, and indeed you can't do that to straight text.

Then why can I simply click the Wikipedia link I posted previously?

EDIT: It turns out that Firefox automagically turns the links on this page into real, clickable links. You are correct, your site is not vulnerable to that sort of attack. I guess I need to check the HTML next time -- I had no idea FF was doing this for me!

It is interesting that Firefox does that (in fact it doesn't with my copy). Maybe it is an option?

Actually, it looks like it is a feature of the FasterFox plug-in. I guess I've had it so long I don't even know what all it does anymore :P