Finally, Webdeveloper Toolbar for Chrome
chrome.google.com
chrome.google.com
It's not as nice/refined as the Web Developer extension of course, for example that 'outline block level elements' readjusts the whole page which it does not do in firefox (which is why I found it useful in firefox, it didn't actually add a 1px border).
You have a nice interface to the DOM. Use it, not some mediocre bundle of bookmarklets as a browser extension.
I do look forward, though, to switching from Firefox once these crucial features -- for me at least -- are in there.