According to the latest release notes for RedHat Seven (the beta version) you can now install RedHat via VNC.

Installation via VNC is now supported. To initiate a VNC-based installation, pass "vnc" as a boot-time option. If necessary, a password can be set by adding "vncpassword=" to the boot-time options. The VNC display will be ":1", where is the IP address or hostname of the system installing Red Hat Linux.