Over the past few decades, many ideas in the field of planning have become almost buzz-words in the popular press, including Sustainable Development” and New Urbanism. With the increased interest in planning, PLANetizen was created three years ago as "a public-interest information exchange for the urban planning and development community." The site features a host of frequently updated links to recent news stories that address one of the facets of planning (such as gentrification), job opportunities, commentary, and conference announcements. Guests to the site may also elect to sign up for their electronic newsletter, and may even choose to have it delivered to any number of handheld devices, including Windows CE or Palm. The site also includes a list of the 20 "all-time greatest planning titles," which includes such familiar selections as "Good City Form" by Kevin Lynch and "Silent Spring" by Rachel Carson.