Usablenet is leading in Top 100K Sites and Top 1M Sites.
Yahoo Search Marketing Analytics has better usage coverage in more websites categories. Including Business & Industry, Shopping, Arts & Entertainment, Internet & Telecom and 79 other categories.
Usablenet is leading in Recreation & Hobbies, Collecting, Outdoors, Weapons and 3 other categories.
Yahoo Search Marketing Analytics is leading in most countries, including United States, Japan, Taiwan, Korea Republic and 29 other countries.
Usablenet is leading in United Kingdom, Spain, Tunisia, United Arab Emirates and 2 other countries.