Google Web Fonts
12,035,783 websites

Google Web Fonts is free to use

https://fonts.google.com/

Google's hosted library for web fonts. Allows websites to choose and use fonts from a free, wide variety of fonts.

VS

X-UA-Compatible
11,141,235 websites

X-UA-Compatible is free to use

http://blogs.msdn.com/ie/archive/2008/06/10/introducing-ie-emulateie7.aspx

Allows a website to define how a page is rendered in Internet Explorer 8, allowing a website to decide to use IE7 style rendering over IE8 rendering.

Market Share by Top Websites

1 Google Web Fonts is leading in Top 1M Sites and The Entire Web.

2 X-UA-Compatible is leading in Top 10K Sites and Top 100K Sites.

Websites Categories

1 X-UA-Compatible has better usage coverage in more websites categories. Including Computers Electronics & Technology, Science & Education, Arts & Entertainment, Games and 12 other categories.

2 Google Web Fonts is leading in Health, Food & Drink, Travel & Tourism, Community & Society and 4 other categories.

Geography

1 Google Web Fonts is leading in most countries, including United States, United Kingdom, Russia, France and 150 other countries.

2 X-UA-Compatible is leading in China, Japan, Germany, South Korea and 8 other countries.