many have complained that www.mysite.com/~user1
would give them an 403 error even after they had added
UserDir public_html to httpd.conf
and had
chown user1.apache ~user1/public_html
chmod 2770 ~user1/public_html
well you have to go a step further
chown user1.apache /home/user1
chmod 2770 /home/user1
Apache had rights to the public_html dir
but not to the dir that held it

!!!!!!For Security Reasons If I were you I would add
UserDir disable root
after the UserDir public_html statement in your
httpd.conf
This will still allow access to the public_html but will
prevent there from being an www.mysite.com/~root
account forced onto your system!!!!!!!!!!!!!!!!!!!!!!!!