ctr-shift-hover for revealing css styles is fantastic, and it's all done very nicely and elegantly. i'm impressed.
i think it would be even more helpful if the hierarchical list of css elements would mention class attributes if there is no id. the way it's implemented now you get something along the lines of body-div("container") - div ("center") - div -div - div - span so if you have a complex site, and the last few elements only have class attributes -- it's not going to be easy to identify them.
it would be nice if they were shown -- with perhaps some visual clue that it's a class name and not an id.