If the comments below were true, you would not be able to search for "Adams North" on Trulia. However if anyone even begins to type in "Adams North, San Diego, CA", Trulia not only has it listed as a neighborhood/area, but they complete the typing for you.
Secondly Trulia uses Google for its maps. Google corrected the "Adams North" mistake about a year ago, yet if you select "map" on Trulia, they are identifying a location that is not a San Diego neighborhood.
To say "Trulia isn't doing it" is false. They promote in their searches and they actively add it as a neighborhood on a map program that does not.