Why isn't Gnus reading my mail?

[Dan Anderson <dan@mathjunkies.com>]

I am trying to set up Gnus to read my mail.  I went through the manual
and think I have figured out what to do.  So I put the following in my
~/.gnus:

,----[ My ~/.gnus: ]
| ;; -*- emacs-lisp -*-
| ;; GNUs configuration file.
| 
| (setq user-mail-address "dan@mathjunkies.com")
| (setq user-full-name "Dan Anderson")
| (setq message-user-organization "")
| (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
| (setq gnus-secondary-methods '((nnmaildir "")))
| (setq mail-sources '((pop :server "mail.mathjunkies.com"
|                           :user "username"
|                           :password "password")))
| (setq smtpmail-default-smtp-server "mail.mathjunkies.com")
`----

But, when I open up Gnus I have the following problems:

1.  The organization  isn't set to "".   It's using Road  Runner -- my
    cable modem provider.
2.  I can't read any mail.  I've got my newsgroups but no mail.

What am I doing wrong?

Thanks for your help,

Dan