The MathJax Consortium has released MathJax v2.5-beta, which is focused on improving rendering speed and MathML support.
MathJax was started in 2009 by the American Mathematical Society (AMS), Design Science, and the Society for Industrial and Applied Mathematics (SIAM). The aim was to develop a universal, robust, and easy-to-use solution for displaying mathematics on the web.
This beta release has been issued so that users can start to test out the v2.5 features. The MathJax Consortium is asking users please to report any bugs that they might find to the issue tracker.
The current release improves the speed of HTML-CSS output by 30-40 per cent (depending on the complexity of the content, with higher gains in more complex situations) and introduces a new preview output (CommonHTML) which provides what is currently rougher, but ten times faster, rendering.
In terms of MathML support, Content MathML is now fully supported and the experimental support for elementary math elements has improved. The release also includes over 70 bug fixes to increase the quality and stability of MathJax.
The beta release is available on the MathJax CDN at beta.mathjax.org/mathjax/latest/MathJax.js. However, this is still beta software and inexperienced users may want to wait for the official 2.5 release which should be available within the next three weeks.