Caterina Fake, who cofounded Flickr with husband Stewart Butterfield in 2004, has a new startup, Hunch, which may be launching soon. But where's the other half of the famous Web 2.0 couple?

To this day, every history of Flickr has an obligatory mention of the "husband-and-wife team" who started the photo site. Indeed, their relationship was a key part of the winsome story that made Flickr so appealing to reporters and consumers. But we've been hearing for some time that Butterfield and Fake are no longer husband and wife.

They have not worked together in years. After they sold Flickr to Yahoo in 2005 for a reported $35 million, Fake almost immediately took an executive role developing new products, while Butterfield stayed at Flickr as the site's often-diffident manager. They did manage one joint launch: the birth of their daughter Sonnet in 2007. Both left Yahoo last year.

Hunch, which we're told is going to be some sort of question-and-answer search engine, could be launching any day. Fake seems to have thrown herself into working at the New York-based as a chief product officer, a demanding job with a bicoastal commute. One of Fake's cofounders recently told an investor not to be concerned with Fake's availability to work, saying she was divorced. If they are, it's not clear if the couple has actually completed the process; a search of public records did not show a divorce agreement, and Fake and Butterfield did not respond to email inquiries. But their friends agree they are no longer together.

Last July, when she announced on her blog that she'd be joining the startup, she noted:

Will you be working with Stewart? No, he's currently weighing various metallurgical opportunities.

And there is this: Fake has posted only one photo to Flickr since last July: a screenshot of the original Flickr homepage. A wave of nostalgia, as she moves on to the new? Butterfield, meanwhile, seems to have no trouble making friends.

(Photo via caterina)