I guess I'm a little late in the day with this, but the porn site posting thing is easy to explain (I think). It's nothing to do with them wanting people here to follow the links to their crappy sites, it's all about Google.
The idea is Googlebombing. One of the lesser-known things about the Google ranking method is that it really, really likes links that happen to use the exact same words. For example, let's say I place links in five web sites to Storage Forum, and the words I link the SF URL from are:
* interesting storage discussion
* great talk about storage
* all about storage
* the best site for storage
* learn about storage
Google finds those links (eventually) and raises Storage Forum in its rankings a little bit. The amount SF goes up in the rankings depends on the "merit" of the sites I'm linking from.
So, if I place the links in a few no-one-ever-heard-of-it sites, they make very little difference to the ranking. If I place them in a prime Google site (i.e., one that Google thinks is popular, and which is linked to by other high-rated sites), then the Storage Forum ranking goes up. Maybe it goes from Google # 142 to Google #131 in the first example; but up to Google #87 in the second one.
Now comes the clever bit: the Googlebomb. This relies on the fact that the Google ranking mechanism just happens to really like links that point to a site from the exact same term.
So, I go back to my 5 no-one-ever-heard-of-it sites and, this time, I link to Storage Forum like this:
* all about storage
* all about storage
* all about storage
* all about storage
* all about storage
Five different sites, none of them worth a blip on Google's radar. They can be total crap sites that get 3 hits a month - it doesn't matter. Because all of a sudden, for the search term "all about storage", Storage Forum is Google #1!
So what's going on with the porn-bot accounts, unless I miss my guess, is that they are trying to get links here (where Google searches now and then) using the exact same link term as they are trying to get on various other sites. And, of course, getting your pay site listed as Google #1 (or even #10) for a term like "great tits" is worth quite a lot of money.
Scumbags.
Delete the bastards, Doug.
If you need any help with them, I am happy to use a little of my famous simian upper body strength to rip them in half for you.
Most people behave much nicer after you tear their arms off.