Michael Arrington at Techcrunch has an article about Riya 2.0. They're going to start offering a visual search engine to allow people to do similarity searches ("find me pictures that look like this"). This is quite a departure from their existing service. (By the way, their site doesn't work with IE7. Shame on them!)

One disturbing yet intriguing application of the upcoming service:

Dating is another (if slightly creepy) use for the new Visual Search engine. See someone’s picture on MySpace that you like? Search on their photo to find single people who look similar and who have profiles up on match.com or other dating sites. Again, Riya makes a referral fee by moving the traffic along.

I'm eager to hear more about the technology, but I expect the Riya folks will keep much of it a secret for now:

• Will this be a pure computer vision problem, or will they use the image's context within a page to help determine similarity?
• Will they allow users to refine their searches by iteratively choosing images that are closer and closer to what they want?
• Will they rank search results just on visual similarity or will they combine other factors like click-through ratios and amount of the referral fee?
• Will they have sponsored links / targeted ads? What does a "keyword" look like when you're advertising next to image search results?