Riya, the Redwood City start-up that is developing technology to recognize the people in your photos in order to let you tag and sort them more easily, has raised $15 million from Bay Partners, according to the company’s CEO, Munjal Shah. That’s a lot of cash.

Remember, this is the company that Google was supposedly flirting with for a possible purchase. But Google didn’t bite, or didn’t bite hard enough.

Perhaps the Riya product needs developing a bit more. Indeed, Peter Rip, venture capitalist at Leapfrog Ventures, and an existing backer of Riya, told us during the last barbecue at Michael Arrington‘s place, that the software still takes a while to recognize a face in a photo. You still have to feed the software quite a few photos of a person’s face before it is recognized permanently, and thus recognizable by Riya in other photos.