OS X 10.8 hosts file completely ignoring new entries. Help!
As far as I'm aware, the /etc/hosts file on UNIX systems is intended to map IP addresses to hostnames and vice-versa. You have not added IP address information for these hosts.

See the man page for more information by typing the following at the command line:

man 5 hosts


You haven't specified how you are attempting to use this file or the records inside of it, so it's hard to say why it was working previously.