Hi,
Thanks everyone for the responses.
I'm familiar with the Spam blacklist extension and how Wikipedia is sharing it by hosting it on meta. We also downloading and making use of this blacklist daily. While the meta setup is a good solution, I'm not sure it's the right one for our set of wikis. I would ideally like to see a solution where:
1. There is only one copy of our blacklist and changes to the blacklist are immediately available to all wikiHow sites. If we can't share a IP block list, having additions to the blacklist be immediately available to the other languages could be really beneficial in a case of a cross language spambot attack, etc. It's my understanding (correct me if I'm wrong) that the meta blacklist is only periodically updated to all of the different Wikipedia sites. Having only one copy also eliminates any synchronization problems.
2. I would ideally like to see a solution where admins don't have to leave their familiar wiki (i.e. Spanish wikiHow) to update the blacklist. We strive to make our wiki as user friendly as possible and as easy to maintain as possible. I think the workflow of expecting an admin to navigate to a different wiki and login to submit an edit to update a blacklist would be an unrealistic expectation for our admins and could be improved. Plus, I wouldn't look forward to maintaining a separate wiki just for the blacklist!
I've written an extension (SpamDiffTool) that streamlines the addition of domains an URLs to our blacklist, most of the edits to our blacklist come from this tool:
http://www.wikihow.com/Spam-Blacklist?action=history
(the edits with the comment Adding to Spam Blacklist come from the extension)
I was thinking it might be possible to extend this tool to point to one target blacklist on, perhaps on the English wikiHow, so that all other edits from other languages would end up in this version. There would be potential protection issues, since ES admins wouldn't have privileges to edit the protected EN page, but I think a workaround for this is doable. Other features for listing and removing entries from the blacklist would also have to be added.
If anyone has any other suggestions or comments, I'd appreciate hearing them.
Thanks, Travis