I remember when I was doing a talk in Melbourne, another developer told me what he didn't like about Atlassian was that they essentially only had one product (was it Jira? or Confluence? can't remember) and almost everything else in their offering set; they bought from other people and re-engineered to fit into their product line.
Having administered, Jira, Confluence and Bamboo servers (all with slightly different installation steps, logging and means to connect to LDAP), what he said made sense.
That being side, I really like Confluence. It's an amazing wiki, even though it's a bit expensive (although they do have free open source project licenses) and kinda resource hog.