There are photoblogs and then there is Boston Globe's news photoblog Big Picture.
This site is literally and figuratively a treasure-trove of screen-filling images captured from all over the planet- and sometimes beyond. The Big Picture, maintained by boston.com web developer Alan Taylor, sources its images from traditional news-gathering agencies like AP and Reuters and from the occasional non-professional contributors. It showcases snapshots of current events like the recent landslides in China and the struggles of the survivors of Pakistani floods in vivid details that transports the viewer into where the action is. At times, the Big Picture captures common threads that bind humanity like Stormy Skies or the joy of photography itself through features like In Silhouette.
I sometimes spend hours on end just wading through 30-40-picture sets. There are quick one-line captions contextualizing each photo. Whether posed or serendipitous, there's a clear perspective in each selected photo that make up each set. Truly, each image evokes the feeling that it is our story, each of us- photographer, subject, viewer/browser- is part of the planet's Big Picture.