CK's done a wonderful job at compiling a visual summary(PDF) from a post a while back in which she asked the simple question:
"What is the single greatest point of value you receive from blogging?"
I'm calling this a "theme" as opposed "meme" because I believe it will spread, but ultimately it's not about CK—it's about all of us who work in marketing and actively blog. You should check it out as it includes the perspectives of all different kinds of marketers who all happen to be blogging. Some of the names you may even recognize. They are:
Vaspers the Grate