Thanks sdayman. Your Wordfence-fu is great :)
@peopleinside sdayman has it right. Wordfence needs to be installed on each blog domain, however if you have a multisite install its only installed on the parent domain and covers all of the sites under it. Example : http://www.domain.com/blog1, http://www.domain.com/blog2, and http://www.domain.com/blog3 would all be covered under the samne wordfence installation.
http://www.domain1.com, http://www.domain2.com, and http://www.domain3.com all hosted on same server would need separete installs (i'm sure you probably knew that but thought I would clear it up for anyone else that came along looking.
Thanks for using Wordfence!
tim