If they keep the Human theme (or a slightly modified theme) that will show Ubuntu doesn't have the means of its ambitions - not because it doesn't have designers (lots of good themes have been created) but because the "managment" can't take any meaningful decision, nor give any artistic direction to the project. It will also be a slap in the face of every body that spend their time and energy creating new themes for Ubuntu, just to see their work is never acknowledged.
I'm not one of those that find Human ugly, but nevertheless, there's a problem if they can't move forward after 4 or 5 years.
I'd welcome a darkish (CDE-like, or dark purple old Solaris theme) - easier on the eyes, and a bit more original than the light gray/white Legacy Windows and OSX themes.
Edit : Dust is indeed the theme I use atm for Intrepid, there's still inconsistencies (Firefox vs Thunderbird) but those would certainly be cleared in a heartbeat if everybody knew they'd chose Dust (unless, of course, a certain benevolent dictator decides he can't live without the antiquated human on all desktop).