more on a9

this business 2.0 article has an interview with the a9.com project lead. the interviewer proposes a really interesting future direction for a9, which the lead unfortunately kinda refutes:

By overlaying what you're looking for onto what you've already found -- and, ultimately, what you've consumed -- A9 aims for the holy grail of search and e-commerce. While others have tried to create personalized interfaces, none has worked so far. Users don't like to answer questionnaires about what they like and what they don't; often they lie. But Amazon already knows who you are -- or at least, what you buy. With A9, the company can factor in what you browse and search for as well.

And the best part, from Amazon's perspective, is that the more things you buy at Amazon, and the more you browse with A9, the better the company will know you. Ideally, it's win-win -- you get better results, Amazon gets more sales.