Here is a little tool for testing the performance of a page.

Just drag this dom depth link into the bookmarks area of the browser and you are ready to go.

And now the fun part:

The link is a minified javascript function that analyzes the current page DOM and generates a google chart API call in a popup.

The graph shows the level of imbrication of the DOM elements and the number of elements for each level. Depending on the purpose of the page having many elements is not necessarily a bad thing, but usually it is.

As an example you can try it on google reader or wave just to see what crappy code GWT generates.

The sourcecode can be downloaded here.