Lastly, I am slightly intrigued by the theme of this spam. It is fairly innocuous (at this point)
That's because there are probably times when the inline links they posted don't work (forum stripped them off) and other times it is just a test/placeholder for a sleeper account to see what kind of reaction (or lack of) comes from moderators. Also- once a user is approved they may also be using the account to try to send Private Messages to other Registered users. The spam or scam will be in the PM, not the public comment. Some forums will not allow a new user to send PMs unless they have posted "X" amount of comments first, so they post bland, innocuous comments to meet the threshold of being allowed to PM others.
I moderate another forum elsewhere and it used to be inundated with this kind of stuff. I now check all emails/IP addresses of new users with a web-based spammer database and just nuke them if they are on it.