Regarding GlusterFS in particular, it's more a distributed parallel fault-tolerant file system than just a shared solution like GFS or OCFS2.
In the context of distributed parallel fault-tolerant file system, GlusterFS were to my mind enough interesting to suggest because it's free, mature enough, backed by a strong community and now also by redHat as it has been purchased by, it's Fuse approach make it quite simple to implement without hard constraints, it's approach correspond to a scale-out NAS file system without metadata servers, and i simply not see real competitors in its area (well, there are excellent software like XtreemFS but with a different approach, here for wide area networks), finally Pacemaker/Corosync/Glusterfs is an interesting HA cluster set.
Whatever, as you left the "shared storage" for the system administrator and you focus on the local storage, what are the kind of use cases for the storage you're thinking about ?
EDIT : i've just saw that CloudFS/HekaFS (http://fedoraproject.org/wiki/HekaFS
) is based on Gluster, is sponsorised by RedHat and present in Fedora, maybe even more adapted to our context and worth to have a look on.