I started the image and let it boot to the gui selector for live session or install only. When the drum sound played, I pressed ctrl-s to start the screen reader and heard the familiar "screenreader on" sound, and it read the options to me. From there, I started the live session, and went into the installer, but orca would not read any of the screens. I also started a terminal window and noticed that it says "window" when I move the mouse over the unity launcher icon, and "unity dash" when I click on it, but nothing in the terminal is read to me either. So I don't think this is limited to just ubiquity.
DistroRelease: Ubuntu 13.10
Package: gnome-orca 3.9.92-0ubuntu1
ProcVersionSignature: Ubuntu 3.11.0-8.15-generic 3.11.1
Uname: Linux 3.11.0-8-generic x86_64
Date: Wed Sep 25 14:04:20 2013
LiveMediaBuild: Ubuntu 13.10 "Saucy Salamander" - Beta amd64 (20130925)
UpgradeStatus: No upgrade log present (probably fresh install)