One thing with the new Outlook 2011 for mac that I really like, is the ability to reply (reply all also) with just a portion of an email. As far as I know this isn’t part of the Windows based Outlook set.
When you receive an email, sometimes it’s useful to be able to hit reply but to not include the entire original mail body, just the portion to which you are wishing to comment upon or draw attention to. It’s simple in Outlook 2011 for mac, you highlight the portion you wish to include in your reply, as normal
Then simply hit reply (or reply all), and your email will instantly include just the highlighted text, but retain the original to/from header information.
Useful feature for me, especially when I want to jump on something somebody said, or praise a worthy comment etc.