JSTalk, introduced by Gus Mueller, is a new tool designed to modernize and enhance AppleScript by allowing users to write scripts using JavaScript while leveraging Cocoa's distributed objects for application communication. It functions similarly to how Cocoa relates to Carbon, using a bridge—JSCocoa and WebKit's JavaScriptCore—to connect with Cocoa, offering improved power and speed. The concept is akin to other bridges like PyObjc and RubyCocoa, making it an exciting development for enthusiasts of both Cocoa and JavaScript.