Script Debugger: You have experienced the script debugger in IE8 beta 1. We’ve made it even better in IE8 beta 2. You can view script in syntax colored code similar to what you might expect in code editors such as Visual Studio™. The console shows all the script errors in a webpage at a central location. We also support the console.log mechanism to log the errors effectively. The Console is extensible for you to add your own commands through custom scripts.
Script Profiler: This is one of the new features of the IE8 Developer Tools. It will help you identify and fix performance bottlenecks in scripts so that they can run better and faster. The Script Profiler comes with an easy-to-use UI and powerful features such as ‘Call Tree View’ and ‘Export’ functionality. The Profiler output can be exported to tools like Excel so you can visualize the execution times through charts and graphs.