I have just clean-installed ubuntu 14.04 + gnome 3.10 (the system is 32 bits since my laptop is just a HP G72 with 3GB of ram). I've also moved back some users data (.thunderbird, some docs, music and photos). By the way: there are two users (both admin - but my wife doesn't fiddle with sudo for sure).
Everything seems to be fine IF ONLY we log in after reboot / start. It takes no longer than 10 secs from entering the password to desktop, which is fine for a laptop some years old.
However, after having logged out (same happens for both users) it is extremely slow to log back again (or login to the other account). I tried (over and over again) to measure the time, but useally after 3 minutes I just go to a console, login as the "stuck" user and "kill -9 -1". After that, login time is fine again. Of couse until I log out...
As a temporary workaround I have
kill -9 -1
rm -rf ~/.cache/ to /etc/rc.local
It helped, a bit at least. Now re-login lasts a minute or so (not several minutes)
Still, it is not much of a comprehensive solution.