I've had two jobs as a direct result of writing for SQLServerCentral and a number of opportunities.
One of our directors gave me an hour of her time to give me some career guidance. My premise was that there is office time, professional time and personal time. For her, what are the boundaries, what are the sacrifices, how do you generate opportunities?
She told me that an organisation will take what it is given so it is up to you to make sure you don't give more than you can afford to give. That is, don't give so much that you burn out. You need to find your own level because what will be fine for one person will burn out another.
If you have the opportunity to speak at conferences then do so. You will become a known face in your field. Always ask about opportunities to be on the panel on "ask the panel" type events. Organisers are usually looking for worthy participants.
Personally, I know what effort goes into writing. To write a good article that you can read in 10 minutes it can take weeks of preparation and research.
A good presentation can easily take that long and preparing for panels takes a lot of effort too. This was something she was keen to stress.
This sort of activity comes under the category of "looking after your career security" which is more important than "looking after your job security"