The knock on Google (NASDAQ:GOOG) is simple. It goes like this:

  1. Come on, guys, it's just search.
  2. Search technology is in its infancy and will be transformed by upstarts that will wipe out any competitive advantage Google thought it had.

Point two is more worrisome, isn't it? It should be. For years, Tim Berners-Lee, a computer science professor who created the World Wide Web as we know it today, has pitched the idea of a "semantic Web" in which data is organized by meaning rather than by content.

I've long believed that the semantic Web poses a huge threat to Google. Thus, the answer to my headline isn't Microsoft (NASDAQ:MSFT) -- although an increasingly hard-boiled (yet creepy) Mr. Softy is getting more dangerous by the day -- but rather a far-off start-up whose sole purpose will be to make your classic Google search obsolete.

How far?
Or maybe not that far off. Yahoo! (NASDAQ:YHOO) got a brain boost in February. Privately held Radar Networks has Twine, which combines search and social networking in the quest for meaning. Baby Breaker Daylife aggregates news and images by topic. All three have taken semantic Web-related steps.

Yet none of these has captured the attention that Powerset has. And for good reason: The start-up recently unveiled an algorithm for searching Wikipedia in plain English. With it, I challenged Google to a head-to-head search-off. The results show Google in need of work but, on the whole, surprisingly resilient.

For example, a search for "paintings of Salvador Dali" at Powerset returns both biographical pages and an elegant array of images depicting Dali's work. A similar Google search lacks the image catalog -- unless you click over to "Google Images" -- but it does bring up the Wikipedia page.

Nevertheless, I found Powerset's results to be richer and better organized. Key words and phrases are highlighted on page results and then organized with sidebar tools called "Outline" and "Factz." 

But is this technology really as disruptive as it seems? It would be if Google were doing nothing to improve its search technology. But a trip to Google Labs and its experimental search tool proves that's not the case.

Performing the Dali query using the experimental search yielded rich views. An "info view" set to show images was at least equal to what Powerset displayed. A "timeline" view provided a decent chronology of Dali's life and work.

My point? Right now, Powerset exceeds Google's primary search engine in richness of results, in my opinion -- but only for the limited subset of data it provides, and even then, not by much.

Not exactly a one-trick pony
The bottom line is that Google's search is improving even as upstarts and peers try to exploit its weaknesses.

Not that users are, um, searching for alternatives. Google's share of the search market rose to 67.9% in April, up from 65.26% a year ago, researcher Hitwise reports. No. 2 Yahoo! fell to 20.28%, and Microsoft's MSN sank to 6.26%. Of the top four, only Google and IAC's (NASDAQ:IACI) gained share.

No wonder my Foolish colleague Rick Munarriz thinks Yahoo! is doomed. I do, too.

Not Google, though. Where others see a one-trick pony, I see a stable of thoroughbreds tied together by the search engine and by a singular idea: to organize the world's information.

Gmail, Google Maps, and YouTube are the obvious tools. But there's also Google Notebook, a digital organizer that collects notes and Web links as well as anything else I've ever used; Blogger, for musings; Calendar, for everything on your to-do list; Reader, for your RSS feeds; Docs, for most of what Microsoft Office provides, yet for free; and so on.

These products matter because the job of "organizing the world's information" can't be achieved simply through search. Users know that, too. DoubleGoo surpassed Yahoo! as the most-visited Web property in April, when its U.S. audience grew by 18% year over year, according to researcher comScore. You don't really think a marginal increase in search-market share explains that rise, do you? I don't, either.

Let's give search and the semantic Web their due. Both are important, and Powerset deserves kudos for moving the needle. But more and more users are turning to Google's tools for an increasing number of tasks. It's going to take a lot more than a fancy Wikipedia search to reverse that.