For those who pay attention to developments in the confusing and constantly evolving world of mass media, it’s a sad first Monday without David Carr, whose Media Equation column provided much-needed updates from the front.  Carr collapsed at work and died last week at 58.  A remembrance column appears in the paper today.  Carr wrote often and well about the growing impact of social media, and the difficult issues of privacy, responsibility and fairness in the digital age.  He also focused on the business side of modern media, particularly the efforts of longtime institutions (like the NYT) to stay relevant and satisfy today’s online news appetite.  His personal story added another dimension to his achievements.  His journalistic success followed battles with many demons.  He will be long remembered, and missed.