I see the first spam appears to have arrived ...

I am not seeing any link, but the post is "Community Flagged" so maybe that hid the link.

Or maybe new users with few posts can't add links anyway.

I'm not sure what the mechanism is to make the links go away. But it looks like at least one person flagged the link. My understanding is that once three regular users flag the post it disappears and goes into a moderator queue. So I'd encourage people to flag posts that are spam. That makes the moderators job easier.

I'll take care of this one now.

Thanks for explaining that Graz, I'll make sure to flag anything suspicious in future. The post I saw was marked "Hidden because community flagged" so I assumed there was nothing for me to do ... but might well be that if I and others, also, flag it even in that state it will hasten its demise! Happy to do that in future.