Outlook was always too busy for me. It was almost designed for people who want to spend their day "living" inside of email and calendar appointments. Ever click on the Journal by accident and get a wizard to set it up? New emails greet you with a "click me" pop-up notification including preview text, a sound, and a little "new mail" icon by your clock. It's like the most important thing you should do right now is stop whatever you're working on and read the new message; mental death for anyone attempting to concentrate on something.<p>I know you can shut this all off and make Outlook quieter, but sometimes coworkers and bosses don't like this. "Did you get the email I just sent you 30 seconds ago?" The thing that bugs me about Outlook more than anything is that its incessant ADD can affect an entire organization and trickle into its blood. It takes a group of rebels to fight against it.<p>This isn't really an issue if you're job is reactive. Customer support, IT getting an email alert that a server just went down, etc... Then Outlook can be really helpful so long as you know how to "tame the beast" with email rules.<p>Exchange is a nice piece of tech (albeit a bit of a pain to setup and configure from an IT's perspective - I've done several builds myself). It "tightly" integrates with Outlook in a properly-configured Active Directory environment. For corporate-hosted email, the Outlook/Exchange combo is pretty tough to beat if you have the cash for it.*<p>In non-corporate land, however, I'm in love with Mail.app. It's so simple and basic. Far less annoying than Outlook. There still are new-mail notifications (easily turned off), though they're less tempting to click on as you don't get a mini-message preview as with Outlook. Search is MILLIONS of times better than Outlook.<p>I think it comes down to a matter of taste and work habits. Some people live and die by Outlook. Others like myself are just plain sick of it for a list of reasons and like something else. It's like OS-wars. Just pick whatever makes you happiest and stick to it. Don't tell others what they should be using or how they should be using it, etc... :)<p>*If anyone has any experience using Mac OS X Server's mail server and Mail.app, compared to Exchange/Outlook, please share!