The RecentChanges page (linked to via the logo in the top right of each page) is the place to start from to catch up with Wiki updates, but (at least for now), it makes no distinction between important updates and minor corrections, so it sometimes takes a little time to wade through.
See TipsForBeginners for a list of some useful pages when starting adding content.
You can edit pages either via the "Edit Page" link at the bottom of the page, or by double-clicking on the body of the page. See EditingTips and WikiQuette for more informations.
Emacs users can also use Unity Dot El to edit unity pages from the comfort and safety of emacs.
Details of the script used to run the Wiki are on the UnityWiki page. You may find it useful to mirror the Wiki locally, so you can access it without an internet connection; instructions for doing this are on Running A Mirror.
Back to GuidedTour, or on to FrivolousPages.