I also have an LDAP setup on a clean Ubuntu 11.10 install - but with local homedirs - and am also experiencing this issue.
The "gsettings get" is also hanging with gdm - so switching to gdm from lightdm is not a surefire fix for this issue, either.
Disabling the 90qt-ally script immediately fixed my issue. Quick tip on this - rather than editing and commenting-out the entire file, it can be disabled by just prefixing it with a non-# - e.g. "cd /etc/X11/Xsession.d && mv 90qt-a11y x90qt-a11y".