As we have WordPress and WordPress MU, both of which are downloadable, by everyone, including hackers, I would like to suggest a new version of WordPress, that is not freely downloadble...
WordPress Security Edition (WordPress SE)
This would be the same WordPress version with additional PHP coding not found in the public version. Though this version of WordPress would be serialized and set as either shareware or commercial, it would be targeted to businesses. Serialized? Yes, serialized, and authenticated through wordpress.org, to prevent unauthorized use.
WordPress SE would have PHP code that would automatically delete Spam, in addition to banning the IP address of the Spam poster. Optionally, WordPress SE could ban a range of IP address, automatically. Also, there would be code to identify an IP Spoofer, which is normally used to post spam onto a WordPress site. Additionally, PHP code would be used to delete posted links, if security was compromised and spam was posted.
Additional, during a massive spam attack, WordPress SE would have the PHP code to put the site to Maintenance Mode or Lockdown, automatically, for a predetermined amount of time set by the administrator. Optionally, WordPress SE could give temporary 404 errors when necessary. These actions would tell most Spam Bots to give up and move on to another site.
PHP code are just scripts. Though what I suggest requires some knowledge of AI (Artificial Intelligency), basic knowledge of LISP is very useful.
Well, WordPress SE is only my suggestion. If anyone likes this idea, please let the WordPress developers know. If a WordPress developer likes this idea, then, feel free to contact me. Thanks.