From Microsoft site, here are current features of the tool.
- Explore and modify the document object model (DOM) of a Web page.
- Locate and select specific elements on a Web page through a variety of techniques.
- Selectively disable Internet Explorer settings.
- View HTML object class names, ID’s, and details such as link paths, tab index values, and access keys.
- Outline tables, table cells, images, or selected tags.
- Validate HTML, CSS, WAI, and RSS web feed links.
- Display image dimensions, file sizes, path information, and alternate (ALT) text.
- Immediately resize the browser window to a new resolution.
- Selectively clear the browser cache and saved cookies. Choose from all objects or those associated with a given domain.
- Display a fully featured design ruler to help accurately align and measure objects on your pages.
- Find the style rules used to set specific style values on an element.
- View the formatted and syntax colored source of HTML and CSS.
I don’t know why Microsoft is not releasing any new version of this tool. This tool was last released on 5/9/2007. Since then no new update has come. If you want to try this tool you may download it from here. And of course do not forget to share what you think about it.