As you can see from the image, the new "Document" Tool window consists of toolbar with a dropdown list of the possible outlining trees, a "Filter" textbox for quickly searching the active tree, and then the actual tree. The button on the top toolbar, next to the dropdown list, controls whether the Document Tool window should be context sensitive or not. When it is, WebCoder will automatically show the proper tree, depending on which kind of code you're editing. For instance, as soon as you go from HTML code to a <style> block, the HTML tree will be replaced with the CSS tree and so on. You can manually change between the trees from the dropdown list, of course. As I said, the combining of the outlining trees seems to be working out fairly well, and it will help make the interface less bloated.
Now back to the HTML tree. As you can see, it has a popup menu attached, which will give you access to some extra functionality. Navigate to will move the cursor to the start of the tag in the editor and focus it. Edit tag will activate the HTML Inspector, allowing you to quickly edit the tag with the mouse. Select tag and Select content will select either the entire tag, from start to end tag (if any), or just the stuff within the tag (child tags, text etc.). The Edit #content is pretty interesting as well. Once you click it, the CSS Inspector will be brought up, and you can edit the clicked selector, no matter where it's currently located (inline style block or external CSS file). If the tag has one or several classes attached to it, through the class attribute, you will of course get access to editing those from this menu as well.
I think that's all for now. Questions and comments are very welcome, as usual :)