This weekend I had planned to rebuild my Mac Book Pro so thought I would try 14.10 instead of 14.04. When 14.10 Gnome has finished the install and reboots I get ..... Missing OS. But when I do the same with 14.04 reboots no problems. Think you have an issue with UEFI and 14.10 gnome. Thought you guys might like the heads up.