Google offers a tool to analyze robots.txt files and another tool that analyzes pages to show which search keywords may have the most weight. Many other tools can do these same things (with several free page analysis tools available), but you can bet that Google offering all of these tools under one umbrella will drive plenty of usage.

Google's offering is part of a larger trend for search engines and search marketing firms to offer free tools to draw attention. In addition, firms are also offering new for-fee tools (especially in the area of keyword research) as search marketing continues to become more important and more competitive.