Two recent stories have set some tongues to wagging on the possible impact of "citizen photojournalism" on professional news photography.

First, technology writer Dan Gillmor has published a short essay called "The Demise of the Professional Photojournalist" on the Center for Citizen Media blog. Readers of the essay have added a long section of comments.

Second, Yahoo and Reuters have announced a partnership to distribute and publish still pictures and video shot by amateurs, as detailed in this New York Times story.