MediaWiki 1.17

New installer
Installer has been completely overhauled for 1.17, a lot of bugs were fixed and new features added:
 * ADDME

ResourceLoader
On a typical wiki, every page view includes hundreds of kilobytes of JavaScript. In many cases, some or all of this code goes unused due to browser support or because users do not make use of the features on the page. In these cases, bandwidth, and loading time spent on downloading, parsing and executing JavaScript code is wasted. This is especially true when users visit MediaWiki sites using older browsers like Internet Explorer 6, where almost all features are unsupported, and parsing and executing JavaScript is extremely slow.

ResourceLoader is a new feature in MediaWiki 1.17 that solves this problem by loading resources on demand and only for browsers that can run them. It also improves client-side performance by minifying JavaScript and CSS code (which reduces the code's size and parsing time), batch loading resources (which reduces the number of requests made), and optionally embedding images as data URIs (which can further reduce the number of requests made).