Directories that rank high in the SERPS for a certain keyword provide not only targetted traffic but also a quality relevent backlink. This is the kind of links Google recommands in its guidelines. So If you want to submit your real estate related website, instead of choosing the directory with highest PR, you should choose the directory that ranks best for that specific keyword.

I used the Google custom search to restrict the search on directories. So far 1277 directories are listed.
Strongest Directories for the Shopping Niche
Strongest Directories for the Real Estate Niche
Strongest Directories for the Jewelry Niche
Strongest Directories for the Celebrities Niche

You can do this search for any keyword you are targetting using the
Directories Link Quality Search: http://tools.enquira.com/link-quality.php

Your feedback is appreciated.