This is a rough version of a "friend inviter" which I hacked together. It sends email to people to invite them to join the wiki (the sending part is not written yet.) It should store a copy of each email and have a place for the recipient to tell the admins if it is used for spam.
Comments are most welcome, I am not very good at making things look nice ;)

Latest changes:

• Added the latest additions panel
• Replaced "subscribe to the newsletter" with "subscribe to the mailing lists"; Added a link to read the latest discussions
• Changed the "Try" button to "Play"
• Added a link to testimonials above "News"
• Removed the "Events" section; added a link under the "News" section to the events page
• Added a "Community Stats" section with a "How do I contribute" link under the stats

Added a new tab in the menu before "Support"

Still missing: Documentation.

Thanks a lot for the suggestions. I've added/modified the following:

• "Latest Releases" panel with a link to the release notes under it
• "News" (which will also include past events) and "Upcoming Events" sections at the bottom of the page
• 2 columns to accommodate more information about XE
• Moved the link to the screenshot gallery from the panel in the second XE column
• A link to an explanatory video