Why verify your domain? The primary reason for OwnerRez users is so that your email address will also be verified. Once your domain has been verified, any emails associated with are automatically verified.
If you own your own domain, say acmevacations.com, you can set DNS records that verify us as a sending server. Once you do that, we'll switch over to sending directly FROM your verified email address -- say bookings@acmevacations.com. Of course your domain will be different, and you can pick any prefix, like your name.