Conclusion: Outlook remains the business email, calendar, and contact software of choice. The 2013 version, though not a watershed, offers welcome refinements.
Pros: Sleek new design. Mail previews. Weather bar in Calendar. Social connectors for richer contact views. Full Exchange support. Integrates with Lync. Peeks give quick access to contacts, calendar, and tasks. Conversation view. Quick actions. Mailbox cleanup tools.
Cons: Expensive as standalone program. Print feature hides some options. No Google Apps connector yet.
Conclusion: Outlook 2013 gets a clean new look, and operates more smoothly. Even deeper social network connections and a few new conveniences make it a top notch email application. But Outlook by itself is probably not sufficient reason to upgrade to Office 2013 or Office 365; it's more of a tag-along benefit. The standalone price of £110 is simply too high, but most users will get it with their £80 a year Office 365 subscription or Office 2013 suite.
Pros: Sleek and fresh design, Useful "quick actions", Full Exchange support, New "sneak a peek" feature, Smart social connectors