I've now been blogging for eight and a half years and it's undoubtedly my most valuable career asset--but not just for its reach. It has a number of ancillary benefits that a lot of people who don't blog might not realize.
I was teaching a General Assembly class the other day on careers and I talked about what blogging does for me, and I don't think I'd really ever encapsulated it in a way that I could advocate to others. I think I need to, because I'm pretty stunned at the number of awesome (and potentially more awesome) people I know that don't.
First off, throw out the notions that a) it takes a lot of time b) that you have nothing to say or c) that you don't want all sorts of information out there about you.
I blog about twice a week and that's more than most people. It usually takes me about a half hour to write something and no more than about an hour. That means skipping like one TV show a week--and that's if you really want to get into it. If it takes you that much more time, then you're being too much of a perfectionist and perhaps you're not doing enough offline thinking. My blog posts are mostly outlined in my head by the time I get to the computer--the result of little bits of trends and ideas I've been bouncing off people throughout the week. Once a week is totally enough--skip one show, or simply pay some virtual assistant $25 an hour to do something you don't like to do that takes up your time. For $100/month, a blog will pay you back multiples in your career.
If you don't have anything to say, you need to read more inspiring things from inspiring people and run with a more interesting crowd. Try going to lunch with thought provoking people more often.
With regards to information about you being put out there and judged, can you really not control your urge to post naked pictures of yourself on your blog? If you can't be professional in public and not reveal deep dark secrets about yourself, then you have a filter problem. You should never be allowed to speak in public anywhere and certainly not on the record at a conference or anything.
Most people think of a blog as reach, but that's the least valuable of all the benefits. Some blogs get a lot of traction, which is great, but it's not necessary for a blog to be valuable to you.
I'd say the biggest benefit one can get from blogging is brain training. I heard someone describe Fred Wilson as "insightful" and it made me think about what the nature of having an insight is all about. Having an insight means putting two things together perhaps before others would--or to see deeper into a concept. What you need to have an insight is a framework for understanding. It's not about raw brain power. It's about pushing all of the lower order thinking down in the stack.
For example, if I were to opine on whether Twitter should be free or paid, it helps to get there faster if I have all sorts of other patterns in my head about what happens to incentives and systems when payments, paywalls and stratification is introduced.
So, first, I need patterns to have insight--and if you're blogging you'll notice that your brain starts observing patterns in a way that it hadn't before. It's similar to the way you started paying more attention to sunsets after you downloaded Instagram. Suddenly, you had the tool to add more utility to them, so they became worth paying more attention to. If you have the platform of a blog, trend watching has a higher utility because you can write about it. Over time, you start seeing more trends--because your brain would have otherwise left them to process in the background.
Having patterns to support insights aren't enough. You need quick recall, This is purely a function of practice. This is why VCs are so quick to size up what you do, comps, competitors, previous examples of success--its because its all they do. Start getting your 10,000 hours of trend matching in now. You'll thank me later.
Getting practiced on insightful thinking isn't just good for blogging, of course. Critical and creative thinking is a useful skill overall--one highly in demand. If blogging is a thinkers exercise bike, getting on to ride makes you more in shape for your next race.
Blogging is also a self discovery tool. You will naturally gravitate towards subjects you like--which is easier and more organic than just asking yourself "What do I like?". I would up specializing in recruiting, in part, because I liked paying attention to and thinking about career development and recruiting--two sides of the same job coin. When I wrote about it, the market told me I might have some insight into it but it also told me when I was stretching or being unrealistic.
This not only helps you focus, but it signals to the market an interest in an area over and above the interest that others have. If you really want to be a VC and you're not blogging about some way to add value to companies, the dynamics of the funding market, etc. then I have to wonder whether or not you're really that interested.
That's where inbound marketing and more specifically conversion comes into play. You're trying to get a job, win customers, get funding, etc. so you're reaching out to people. When they get your email, click to your Twitter profile, or check your LinkedIn, what do they see? Are they going to see a living example of how your brain works or just a resume. If you cared about conversion, as a knowledge worker, I think you'd want a brain portfolio.
Lastly, my blog is my intellectual Github account. It's the social depository of what my brain is working on. It's open source. You can grab from it, add to it, ask questions, etc. Each post is a reflection of a line of thinking in progress, one that will undoubtedly need refactoring later on.