I believe they are getting better, but you are right, who wants to search for "almost" all homes? I don't care if it is 2 million or 20 million, if there are more on the MLS, you are missing the boat.
The answers below are correct. Except in a few rare cases, Trulia does not receive listing information from the MLS. Rather, listings are submitted to us by brokerages, brokers, agents and web vendors. While this does mean that we don't have complete coverage in all areas we currently have over 2 million for sale listings in our database and our coverage continues to grow each day.
Customer Service Representative