#Street: Just the street or the number and the street? I'm guessing you want number and street because you ask for apartment number. (Added upon completion: The listing doesn't display number, but the map has the point correct. I like the choices you make on what to display and how; I didn't like being confused on what to enter.)
#City and ZIP: Just ZIP and lookup City/State or ask for all three: City, State, and ZIP. Don't do things that are different just to be different.
#Room Type: Is my Living Room a Shared Room? Probably, but don't make me think, I'm drinking. Perhaps add a few options to the drop down.
#Name of Space: Why only 15 characters? I can't fit "Pull-Out Sofabed" there.
#Availability: The calendars are confusing. I wanted to test by just listing it for the weekend. Perhaps your default should be "never available" instead of "always available", then have me chose days. To make the weekend the availability takes three time frames.
Here's my listing: http://airbnb.com/airbeds/show/5703
I know you ABNB people are here on HN and I want to talk to you. E-mail me or I'll get the TicketStumbler guys to stab you. That is all.