professional blogging as a blogger with "an interest in a subject..." to the point that the professional blogger, "has an interest, a professional objective, and a plan to achieve it."
We've discussed the idea of planning more than once, on this blog. I recommend a plan - not always a full-blown business plan to get you started, but a plan that includes what you want to do, how you will do it, and why it's worth doing. That goes for being a professional blogger, also. Planning is vital to your success. Those who stumble along without a plan...will be trailing behind those who sit down and think it through.