Compete.com, a six-year-old analytics firm, is formally debuting its public data tool tonight. Searchers can input any site on the web to get numbers and trend graphs for total U.S. visitors (absolute, not relative), rank among all sites, pages viewed per visit, and average length of stay. The company gets its data from a panel of about 2 million opt-in users, similar to comScore. Nobody believes anything in this space, unless of course it makes them look good, so it’s a hard row to hoe. At the least, we hope the competition will make measurement more accurate and transparent.