As social marketing has gone thru the typical e-lifecycle phases (germinating, then exploding, then backing off a little into a sustainable, somewhat quantifiable discipline), blogging itself has peaked as a phenomena (you HAVE to blog - GO BLOG!) and then contracted a little.
When blogging was at its peak, and everyone was blogging, the blogscape was littered with blogs that had 4 entries then died:
1) Work
2) then Family
3) then the Dog
4) then a Family Vacation
The good thing about the blogs that truly live today is that they've become more relevant (compared to the blogs that littered the blogscape in the past), and that is the key. When blogging, make it relevant. I'm too busy to follow blogs that are irrelevant...