Looking for a house online usually implies viewing dozens, even hundreds of pages to search for the perfect home. Quite an opportunity for ad networks with real estate-related inventories. According to the National Association of Realtors, 84% of home buyers search online.

On top of the real estate search are Trulia and Zillow. Roost (recently out of beta) operates in a smaller league in terms of popularity, but this real estate search engine was created by the team who launched Kayak, probably the most practical travel search engine on the Web. In a more offbeat philosophy, Realius offers to discover new homes through gaming.

Up until recently, those search engines were our destination to engage in a serious search for a home. Things could play out a little differently now that Google Maps launched a real estate search feature.

So, from today, if you enter a query like < > on Google Maps, you’ll see that we make it easy for you to see all your results on a map with a one-box that will take you to real estate listings. Previously, you had to specify “real estate” from the search options menu, but now we’re making it easier to find available listings

So is Google Maps getting in the real estate search business, and crushing smaller search engines in the process? Kind of. Obviously, the real estate search feature will very soon be integrated in Google’s universal search results. The one-box you see in the sidebar of Google Maps holds the same content that should be delivered in a classic results page. However, as Google states:

Is Google a broker? A national MLS?

We’re neither. Our role is to connect users as quickly as possible with the information they need. People come to us looking for all kinds of information, including housing listings, comparable pricing, and how to find an agent or broker in their area. In all cases, we want to deliver these users to the industry experts who can provide the most useful answers.

Google’s going to play it the way it always does: Google is the origin of a search online, sos real estate search professional will have to do two things to compete on Google’s grounds: 1. Connect their database to the Google’s Base to constantly provide Google with the freshest homes on sale; 2. Use Adwords to compensate for a weak natural search presence. If Google can show that real estate search very often start from google.com, then their real estate search feature opens a new multi-billion advertising revenue channel for the not evil-at-all search company.

On the other hand, this will probably highly increase the competition in the real estate search arena. First all search engines will need to hook up their database to Google, and obviously the largest players with heftier marketing budgets will monopolize the top searched keywords and until the competition dries out. I know, I’m oversimplifying.

How do you think smaller real estate search engines will adapt to this new real estate leads catalyst that Google is slowly unveiling?