Google (NASDAQ:GOOG) already has your eyeballs. Now it wants your loan requests, too.

The world's leading search engine is readying an entry into the mortgage-quote aggregation business, according to niche leader LendingTree.

Tree.com's (NASDAQ:TREE) LendingTree made the revelation when it filed a motion for a temporary restraining order and preliminary injunction this week against Mortech -- a mortgage-software specialist that helps power LendingTree's site for comparison quotes on loans. Apparently, Mortech is also working with Google for a competing platform.

"Mortech, whose technology helps automate lender offer pricing, violated its contractual covenants by partnering with Google to launch an online mortgage loan aggregator service similar to LendingTree," claims last night's press release from LendingTree.

Of course, even if LendingTree prevails, there's nothing to stop Google from going with a rival provider or simply hiring away Mortech engineers for an in-house solution.

The bigger question to ask is why Google would want to go in this direction in the first place.

There's nothing wrong with LendingTree's model. The company has been the gateway for 25 million lending requests and $185 billion worth of loans over the years. But what becomes of Google's lucrative paid-search business with loan providers if it goes this route? It won't lose lenders as sponsors. They'll simply go from bidding on search-result keywords to jockeying for position and paying for hyperlinks on comparative listings. The result would be more useful for consumers.

The rub is that it may lose LendingTree and its aggregator rivals as sponsors. Why would they turn to Google for leads if doing so simply fattens up a competitor?

This is also a warning shot to other aggregators. Whether it's eHealth (NASDAQ:EHTH) for health insurance, Internet Brands' (NASDAQ:INET) CarsDirect for automobile purchases, or The Knot (NASDAQ:KNOT) for wedding-service providers, Google may be invading your turf next.

It may be refreshing to see Google diversify the way it delivers leads to advertisers, but Big G also has a brand to protect. If Web users begin associating Google as a place to go for loan quotes, will it lose relevance as a conventional search engine?

Why didn't it just buy Bankrate (NASDAQ:RATE) when it had the chance, so it could get a killer view of the industry instead of starting from scratch?

What's next? Home Page A-Loan?

Other ways to get off of my cloud:

Google, The Knot, and Bankrate are Motley Fool Rule Breakers recommendations. Try any of our Foolish newsletter services free for 30 days.

Longtime Fool contributor Rick Munarriz isn't calling for a search-engine search party, but he may as well. He owns no shares in any of the stocks in this story and is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.