You may already know this, but Amazon.com just launched A9, the beta version of their much-anticipated entry into online search.

I find A9 fascinating and I recommend that you use it as your default search tool for at least a while to understand what this might mean. In particular I’d suggest downloading the toolbar version which adds some really unique features you need to experience.

Looking past the god-awful colour of the site (which isn’t that easy), the application does some truly brilliant things and starts to answer the questions we’ve been asking about how and when personalization and collaboration will be integrated into search.

If you do an A9 search for say “Internet Marketing in Canada” you get a page that looks a bit like Google (it seems to be using Google’s page results at this time) but with some interesting enhancements. For example, there is a “Site Info” button that allows you to access Alexa information with meta data about the sites listed. One data point provided — similar to Amazon’s book recommendations — states that “people who visited this site also visited…”. And because this is Amazon, there is a separate pane available for book search. And since book search integrates their “search inside the book” technology, it means that A9 allows you to search online AND offline knowledge.

The most interesting feature of the site is its use of personalization. Once you log-in to A9 using your Amazon log-on the site will begin to remember past searches for you and display them on the home page. The toolbar also keeps visited page history and I’m sure that some back-end manipulation of results based on this information is (or will be) happening.

A peek into the potential power of personalization is given in A9’s ability to add to search results the last time YOU last visited a site listed in the results. I just did the above search for the second time and found “clicked 21 hours ago” added beside a link that I had indeed clicked 21 hours ago.

While the site is still in beta and clearly needs some design and UI work, I have to say I’m pretty impressed.

I’d be interested in your impressions on this and some analysis around the implications for Google and Yahoo! of Amazon entering the market.

One big problem I see is that A9 doesn’t lend it self to wordplay like Google does. Will we say “Just A9 me” once we start “A9ing” things?