The former second-class citizens of the programming world have leaped to the fore, changing the face of enterprise software development. With the rise of Web 2.0, scripting languages (also called dynamic languages) are now often considered important tools in a developer's arsenal. That's a far cry from than their old reputation as lesser tools for those who can't handle "real" programming.

Dynamic languages are certainly popular. Almost 70 percent of the 1,200 developers surveyed by Evans Data for its most recent Global Development Survey currently use JavaScript, the most popular dynamic language, with fifteen percent more planning to adopt it. PHP is used by just over a third of developers, and Perl has captured about a quarter of developers (though Perl is much more popular in North America, with 36 percent spending at least some of their time using PHP).

However, like any other tool, dynamic languages are not necessarily interchangeable. Each has its place in a programmer's toolkit. We asked a group of luminaries in the scripting world for their perspectives on the current state of the scripting universe, and how it has changed since we last looked at the scripting language scene in 2005.

• Norris Boyd is the creator and maintainer of Mozilla Rhino, a JavaScript implementation for Java. Boyd was part of the JavaScript team at Netscape. Today, he is an engineering manager at Google.

• Richard Dice is the president of the Perl Foundation, the organization which has responsibility for Perl's legal, organizational, technical and administrative infrastructure.

• Jeff Hobbs is director of languages and Tcl tech lead at ActiveState Software and a member of the Tcl core team.

• Steve Holden is chairman of the Python Software Foundation, and author of Python Web Programming.

• John Lam leads the IronRuby team at Microsoft.

• Rohan Pall, representing PHP, is a consultant who has been programming Web applications for almost a decade.