If you like your musical analogies, then this article should be up your street, as it makes the compelling case that we should think of our blogs as 'singles' rather than albums. In other words, individual blog posts should be your focus rather than the blog as a whole, since today's reader tends to pick and mix from various sources, rather than faithfully returning to the same blog.
As a blog owner, this is both challenge and opportunity. The decline in true “fans” who will visit the blog daily means you have to replace yesterday’s readers with a different group of readers today. But, because most visitors are not coming back over and over, you can adopt a much broader editorial approach without fear of confusing or upsetting the community (in the album era you had to worry more about thematic blog consistency). The evidence of success for today’s blogs has changed too. RSS subscribers, comments, and repeat visitors were previously used as important effectiveness proof points. Those have been replaced by new visitors, time on site, and social shares.