Usablenet is leading in Top 10K Sites, Top 100K Sites and Top 1M Sites.
Yahoo Search Marketing Analytics has better usage coverage in more websites categories. Including Business & Industry, Shopping, Internet & Telecom, Arts & Entertainment and 83 other categories.
Usablenet is leading in Accommodation & Hotels, Death, Recreation & Hobbies, Energy and 10 other categories.
Yahoo Search Marketing Analytics is leading in most countries, including United States, Japan, Taiwan, Korea Republic and 38 other countries.
Usablenet is leading in United Kingdom, Spain, Ireland, Virgin Islands Republic and 4 other countries.