Unfortunately we are again under attack by SPAM-bots, linking to porn and "free software" sites. I hope no one is dumb enough to follow such suspicious links in the first place, but as I have personally deleted two in the last two hours and I know other admin have also dumped some, for the time being registration will go back to being manually approved until we have time to check for updates etc.
Sorry for any inconvenience caused to genuine new members.