Rich Barton, the founder of Zillow, a site that publishes information about specific home values, has launched his next site which aims to do the same thing to with salary information. Glassdoor.com, which launches today, publishes salary information on specific positions within specific companies. Much like Jobvent.com or TheFunded.com, which provides user-submitted reviews of venture capital and private equity firms, Glassdoor also publishes reviews of companies. The company, which has raised $3M from Benchmark Capital, does not currently publish job openings or allow people to apply for positions within companies, and revenue is generated strictly from advertising on the site. Without a doubt, if the site can gain traction with users and provide a wealth of accurate information on a ton of companies, it will be a successful little niche site. I am not sure it will ever become a wildly successful, stand-alone site, but it could certainly be an attractive content category within another job or career site.