Google Base, not yet live at base.google.com, is "Google's database into which you can add all types of content," according to screenshots and firsthand sightings from when the site was sporadically online. Register a Google account (or use an existing one for services such as Gmail), enter a category such as real estate or reviews, key in some attributes, and the post is included for up to a month in Google Base. The entries are then distributed through the search engine, Google Local, and other Google properties. Think of classifieds at first as a model, but you'll need to think far more broadly to get a sense of what Google has in mind.

Using AdWords, every business can participate in a democratic form of advertising. With Google Base, every person with an Internet connection can participate. Selling your car? Use Google Base instead of eBay or your local paper. Selling a home? Give the local paper and Craigslist the runaround. Looking for love? Advertise yourself on Google Base instead of Match.com. Posting a job? Try Google Base instead of Monster or Craigslist.

It doesn't matter what you're selling, or listing, for that matter. Other categories include event posts, reviews, news, and recipes. Whether your content is commercial or informative, you can post it on Google Base. In turn, everyone else can find it there.

Consider a personal example. I go to Amazon for book reviews, CNET for consumer electronics reviews, eBay for opening day Mets tickets (yes, they do sell out), Craigslist during my annual Manhattan apartment hunt, FoodNetwork.com for recipes, Orbitz, Expedia or American Airlines for travel, LinkedIn to look up business contacts, and various sites for online shopping. At every one of those sites, my first activity is searching.

Google Base aims to turn Google into the single source for any site where you'd ever search, raising a middle finger to every vertical search and local information site in the process.

There are, of course, many obstacles to this goal. For one, each of the other sites mentioned has developed a strong following for any number of reasons, and all have built a high degree of trust with their users. Whether it's appreciating the free shipping and recommendation engines at Amazon, the auction system at eBay, the stark look and feel of Craigslist, or the content at CNET, people have a relationship with these properties that won't be easily replicated.

Data from Hitwise, courtesy of Lizzie Babarczy, further illustrates the challenge. In Hitwise's "shopping-classifieds" category, Craigslist is No. 1, with 30.17 percent market share. Of the rest of the top 15 sites, 12 are Craigslist local properties (the two other sites, Recycler.com and Adquest3d, have a combined 2.67 percent of the market). Then look at auctions. eBay's sites have 95.33 percent of market share for the week ending October 22. The No. 5 site? Amazon auctions, with a 0.34 percent share. One area where Google has a foothold is with comparison shopping sites, though Froogle attracts less than 9 percent of visitors for the category, settling for a sixth place ranking (albeit in a category where the wealth is spread more evenly).

Entering the fray won't be easy. Then again, people often find their favorite sites through search engines. It's what John Battelle, in his book "The Search," refers to as "recovery" (as opposed to finding something new, labeled "discovery").

The Google Base business model is also anybody's guess. Whenever it launches, it will likely be free for all (and perhaps a free-for-all). That model would be similar to that of Google Desktop: give it away, but make up for it in increased market share and searches per user. This could conceivably cause problems for its AdWords business. If a small business can market its products and services through Base for free, why would it use AdWords? There are obviously some kinks to work out. Also, realize that until Google Base goes live, almost all of this column is speculation.

Then there's the local search quandary. Google Local is far from perfect; if you look up restaurants in any area you know well, you'll likely find glaring omissions and mis-categorized listings. The maps themselves are so good that users are continually awed by them, but Google must get as good at local search as it is with mapping to make Base work, as most categories for Base posts involve a local element.

Google Base will probably tie into other Google initiatives, including local search, Froogle, the anticipated online payment system it's developing to rival eBay's PayPal, and the Wi-Fi network rollout (first San Francisco, then the world). It will require coordinated efforts unlike anything Google has had to attempt to date. Some of its services are connected, as Google News and Froogle listings sometimes appear atop the engine's natural search results, but that is nowhere nearly as complicated as the operation Google will need to pull off with Google Base.

Battelle presciently writes in "The Search," "If you add in every small business in the world--and believe me, Google is thinking that way--you can sum up Google's ambitions in the commercial world as this: the company would like to provide a platform that mediates supply and demand for pretty much the entire world economy." He then adds, "Even more fascinating, as more and more buyers and sellers come online, searching either for customers or for products, Google's AdWords morphs from an advertising play into something more like eBay's model."

AdWords itself isn't morphing. What's changing is Google, and as Google changes, so does access to the world's information. With Base, Google is creating the VolksAdWords, the AdWords for and by the people. You're either in or you're out.

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