Vents, speakers, and logo are all right there. Well, the speakers aren't located directly there, but the sound is pushed out through the bottom.
I think it'd be more than feasible to make it look similar to the thunderbolt display, where it's a fraction of the size and isn't aluminum but glass across the entire front. But then it wouldn't be as obvious as to which of their products you're using. Apple is all about being iconic after all.
The chin is distinctive and certainly associated with iMacs.
If it were my design choice, however, I'd get rid of it and use a deeper enclosure to house the items behind the chin. Allow room for larger speaker/cooling openings at bottom/sides. And also user access for RAM and other service needs.