Browser Support

The font-feature-settings property is currently supported by Firefox 4+ and Internet Explorer 10, beginning with Preview 4. Note that because Firefox and IE implemented different versions of the draft the value syntax they accept is different. For example, enabling kerning in both browsers requires the following:

-ms-font-feature-settings: "kern" 1;

-moz-font-feature-setting: "kern=1";

More information about –moz-font-feature-settings see -moz-font-feature-settings.
As CSS3 Fonts moves along the standardization track we expect more browsers to add support for font-feature-setttings as well as the more author-friendly font-variant properties and values defined in the module.
Also note that the property applies to all font families, whether Web fonts downloaded through @font-face rules or local fonts referenced by name.

Demos

Our IE Test Drive site includes advanced OpenType feature demos from Monotype Imaging, FontFont and The Font Bureau. They demonstrate the variety of typographic designs available in modern fonts.
You don’t need any special fonts to try this. Windows 7 includes a number of OpenType-enabled fonts including Calibri, Cambria, Consolas, Gabriola, and Palatino Linotype. In the Windows 8 Developer Preview, we added OpenType features to Segoe UI and the Web-safe fonts Arial, Verdana, Georgia, Times New Roman, Comic Sans and Trebuchet.
We are excited to give Web authors access to all the OpenType features built in Web fonts and look forward to an even broader range of typographic design on the Web.