While much of the IT world (especially Microsoft) has been focused on Google’s foray into the enterprise apps market, the Mountain View, Calif.-based company has been quietly working behind the scenes revamping its flagship product, the technology that propelled it to the heights of Internet stardom in the first place, its Internet search engine.

First, Google introduced yesterday a new design to its homepage, however subtle. Links to various forms of search mechanisms –- such as images, video and news-– no longer sit directly above the Google homepage search box, but now live in the top, left-hand side of the page.

The more interesting development, however, is Google’s move to what it’s calling universal search. The idea is to integrate all forms of content into one set of search results. So results of a search for Microsoft chairman Bill Gates, for instance, should include not just the most relevant Web sites, but also videos, news, books, etc., in one ranked list.

 “With universal search, we’re attempting to break down the walls that traditionally separated our various search properties and integrate the vast amounts of information available into one simple set of search results,” wrote Marissa Mayer, Google’s vice president of search products and user experience, on the company’s corporate blog yesterday.

In reality, though, the universal search initiative appears to have a few kinks. When I performed the above search for Bill Gates, the results on the first three pages were nearly all related Web sites and news. There were no books, images or video. This could simply mean that Google determined that the related Web sites it turned up were simply the most relevant results, regardless of content type — but that would seem unlikely.

Additional tabs that group search results by content type did appear at the top of the page, another new feature Google unveiled yesterday, so with an additional click I was able to see books, images and videos results.

Mayer did write that Google’s evolution to universal search, which began back in 2001 and has involved more than 100 Google developers and designers, is only in phase one, which may explain the results of my Bill Gates search. Mayer wrote that additional universal search enhancements will be unveiled in the future, though she set no definitive timeline.

Reaction to universal search have thus far been mixed. In a post titled “Google Universal Search: Intriguing and Confusing,” PC World’s Harry McCracken wrote, “Google Universal Search doesn’t yet exhibit its universality in any particularly predictable fashion that I can discern.”

Over at Publishing 2.0, Scott Karp worries that Google’s universal search will merely increase the company’s stranglehold over media content on the Web, writing: 

“That means links from Google News and YouTube videos (playable right in the search results!) will be included in Google’s all powerful top 10 results for any given search. The consequence of this change is that Google will drive more traffic through Google News and more traffic to videos that are distributed through YouTube — and that means Google will become an even a greater gatekeeper to media company content than it already is.”