There is some inconsistency in the wording that kind of bugs me. In the following...

 - Servers
    - [tag:hardware]
    - Operating Systems, including [tag:linux] [tag:windows-server-2008] [tag:freebsd] [tag:solaris]
    - Server Software, such as [tag:apache2] [tag:exchange-2010] [tag:sharepoint]
    - Virtualization, including [tag:vmware-esxi] [tag:hyper-v] [tag:kvm] 

... we go from using "including" to "such as" and back to "including". The meanings of the words/phrase in this case are essentially the same, so we should settle on one or the other. I propose cutting out "such as" and changing it to "including" and using that for all future instances where warranted (I'm thinking specifically of John G's proposed edit).