I admin a multisite installation of WP 3.2 with just over 3000 blogs and users in an EDU environment. I currently use WP-SpamFree and SI-Captcha Antispam together to prevent comment spam. It works quite well.
However, I noticed that development on WP-SpamFree has apparently ceased completely. Obviously, I want to continue updating WP core, and now I have no guarantees that SpamFree will continue to work with newer versions of WP.
Do folks have any suggestions for good (free?) anti spam alternatives? I really need plugins I can simply mass network activate - a set it and forget it scenario.