perlnews dws Yahoo! has to deal with problems of scale that many sites don't. They've grown up with a combination of proprietary and Open Source software, and are shifting more towards Open Source. For a bit of history on their technical underpinnings (and a pitch for PHP), see Michael Rawdin's presentation at PHPcon 2002, available on-line at [http://public.yahoo.com/~radwin/talks/yahoo-phpcon2002.htm]. <p> Of note here is that they have 3 million lines of Perl in their codebase. <p>