The rendering of MathJax equations in Opera 10.61 on the Mac has issues: spacing is incorrect on occasion, fraction lines are longer than they should be -- see the attached screenshots. This affects both web font and image rendering.
User Agent: Opera/9.80 (Macintosh; Intel Mac OS X; U; en) Presto/2.6.30 Version/10.61
Tested against SVN 592 and the version of MathJax installed on the website. Although I can't attach screenshots at this time, I can confirm that this also affects the Windows version of Opera 10.61.