MathPlayer is by far and away the most used MathML renderer around -- in the 27 months since MathPlayer 2.1 was released, 615 million expressions on 29 million pages have been rendered by MathPlayer! I'm happy to say that we've only had a few bug reports since 2.1 was released, some of which were fixed with intervening bug fix releases. We've fixed many of the remaining ones with this release of MathPlayer 2.2. We've also taken some big steps in 2.2 to improve our font support. When the STIX fonts are finally released in a month or two, MathPlayer 2.2 will be able to make use of them. Even without them, our improved font support makes expressions look much better, as you can see in the screen shots below:
One thing that hasn't changed with MathPlayer 2.2 is its price -- it's still free. You can update your version of MathPlayer by visiting our MathPlayer downloads page.