should i be alarmed/wary?

[ak]

it all depends on what version of vbulletin your using.

Here is 4.x
[GlowHost] Spam-O-Matic - Spam Firewall stops forum spam - vBulletin.org Forum
Here is 3.x
[GlowHost] Spam-O-Matic for vB 3.8 (StopForumSpam, Akismet, Auto-Moderation and more) - vBulletin.org Forum

[Tim]

yea question is should i ban them? They don't offer my forum any value

Yes, no question about it. Delete their spam then nuke them.

I would remove html/bb code in signatures or setup usergroup permissions (if you're on vbulletin):

Admin CP > Usergroups > Usergroup Manager > Edit Usergroup > Signature Permissions

Also keep an eye on visitor messages because they'll spam this part of your forum too. I see very little value in visitor messages (unlike PMs) so I'd switch them to moderated, otherwise you'll just be wasting your time deleting stuff.

Good luck.

[leporello]

100% ban. They're just Xrumer or similar programs that automatically pickup footprints of forums on the internet and autospam them with profile links.