Carlo posted a comment on the previous post here, and a post on his own blog describing the importance and benefits of blogging, in the context of a biology PhD as both he and I are immersed in. He raises some excellent points, and I highly recommend you read what he has to say in his own words.
One point that I think I mentioned in passing in the previous post, and that Carlo also covers, is the need to restrict blogging and similar quasi-procrastination in time and effort devoted, to avoid taking away from "real" work. I've got a few minutes here between lunch and a meeting, and the other activities I need to get done today all require hours-long blocks of time, so I don't feel this little post is stealing time from proper work.
It's moments like this that I will be using for blogging. I often work at school until quite late; over the last few weeks I've arrived at home, with thoughts of a late dinner on my mind, at 10:00pm or later. I'm not complaining about the work-load, but I am trying to explain that I don't normally have evenings available for longer, more carefully composed posts.