If you're upgrading to Mac OX 10.8 Mountain Lion but are concerned over its compatibility with your copy of Microsoft Outlook, or the full Microsoft Office suite, then worry not. Microsoft have published a blog post confirming that Office for Mac 2011 (which includes Outlook 2011) is fully compatible with 10.8 Mountain Lion.
"The Office for Mac team is happy to announce that Office for Mac 2011 is Mountain Lion ready! We've been working with Apple to ensure a fantastic experience for our users."
The posting states that users need to make sure they have Mac AutoUpdate enabled to ensure smooth running. This is because Gatekeeper (part of 10.8 Mountain Lion) doesn't allow updates to run from the desktop.
Customers with hosted Microsoft Exchange Classic or Executive mailboxes receive the latest version of Outlook for PC or Mac free as part of their subscription; available from their email control panel.