Here is a great plugin which allows the admin to choose any number of fonts from the Google Webfont repository, and use them within the tinymce content editor.
The fonts are rendered in both the tinymce content editor box (real-time) and the front end of the website. Additionally, the font is also properly rendered in the font-selection dropdown box... giving a live preview of the font.
The plugin is easy to use, and requires just one simple copy and paste line of code from the Google webpage.
Complete instructions are included in the plugin admin panel settings page.
You can check it out by clicking the link below: