For just over 2 years now, I have had my email domain hosted by google. It has been a great expereince. The service is ALWAYS up and is always getting better. I started out and Google offered something like 2GB for the mailbox. Which is quite a bit. Now it is just shy of 7GB and I have access to a variety of additional features. Best of all, since I am a beta user.. my service will always be free.
So.. the point of the story is.. if you have your own domain, you need to switch to Google Hosted apps for your email. (http://www.google.com/a/help/intl/en/index.html)
Addendum: The first two objections I can think of are.
1. But I love my Outlook. Well the good news is, google offers POP and IMAP support so you can continue to use OL if you have to.
2. My employer/school/library/ISP/whatever blocks access to the site. Well.. that would be a problem with any of the major email poviders anyway. You could always setup an SSL-VPN tunnel to proxy the traffic through.