Jive Software is another company that makes enterprise social software. I first became familiar with them while being an active user of the VMware community. They have a very robust application that defines what a social network should be. They have strong user profiles, blogs, documents, forums, and a highly-configurable layout. They recently had a Jive Roadshow where they gave a lot of great information on not only starting a community, but estimating the value of an enterprise community. Like most of these software companies, they recognize the huge potential of SEO but engineering requirements overshadow SEO so sometimes they lack even the simplest things in that regard.