The UX has areas clearly neglected. For example in apartments there is a trashcan icon to hide a listing. But, it's inserted at the end of the description. If the description is long then the button does not appear.
Another is the categories. In SF, SOMA and Mission Bay arguably need to be separated but craigslist only lists SOMA and groups Mission Bay in with it. That's one of several areas that need to be split
I used it a ton over the last 6 months trying to find an apartment but in the end I found the apartment on apartments.com ... which is far from perfect but has some features arguably more suited to apartment hunting.
That I think might be the point. Different products can benefit from unique features