Support of upstream, community-built packages is pretty nebulous. If it builds, with little or no work, typically we package it. Actual support, as in help with problems, comes from the "community."
Niels and I discussed building glusterfs-5 for C8 and decided we'd wait and see if anyone actually asked for it.
Typical places to reach the CentOS Storage SIG people would be the #centos-devel channel on FreeNode IRC, the centos-devel@ and/or the [hidden email] mailing lists, and also here, to a lesser extent, on [hidden email].