Outlook 2007 supports automatic discovery of e-mail settings - in fact, it tries to force this feature upon unsuspecting users, making it difficult to bypass. However, if you can get it to work, it's pretty sweet.

Unfortunately, getting it to work is pretty obnoxious. It's a lot more complicated than it seems like it ought to be, and I've run into several issues: first, unless you shell out some cash for special SSL certificants on every domain you host, your users are going to get a strange security warning asking about a redirect to an HTTPS URL. Second, the best way to set it up for multiple domains (using SRV records) doesn't work unless you have at least Office 2007 Service Pack 1. Third, there is no way to specify the use of TLS instead of SSL. Finally, if you happen to enter your password incorrectly and cancel out of the setup, the advanced settings all revert to non-working defaults, which you might not notice because the other settings look correct.

But after two days of fighting with it, it works!