Real estate mapper Zillow has just become the latest Internet company to put an IPO into the pipeline. The company filed a statement with the SEC that will let it sell more than $50 million of stock. The Seattle-based company, which maintains interactive maps of house prices, did not reveal how many shares it would sell or what price it would sell them at. But its S-1 form indicates it generated $30.5 million in revenue in 2010, a 75% growth over the previous year. Zillow isn’t profitable yet, but it is closing the gap. In 2009, the startup had a net loss of about $21.2 million. In 2010, it lost $6.7 million. Zillow is only the latest tech company to file for an IPO