There has been a lot of talk in the last year about the usability of the MediaWiki software. Today, the new functionality created by the Usability Initiative has been rolled out. Have a look at today's English Wikipedia main page..
It not only looks good, it also makes it easier to understand what you can do. Given the large percentage of people who just do not appreciate that they can edit a page, it is a big improvement.
When you want to be part of the future of Wikipedia today, you have to change to the "vector" skin. Another neat feature is the "enhanced editing toolbar" that you can enable on the "editing" tab of the user preferences.
At this stage the usability improvements are available for all the "left to right" languages. Because of incompatibilities in IE-6, some more work is needed before it will become available for languages like Arabic and Hebrewl.
All in all, it is a happy day because you can see the shape of things to come for all of us and you can experience it now. When you find any issues, this is where they are happy to leaarn about it.