I believe this is the case even more so for developers than other careers. There's a number of reasons why I absolutely agree with the post.
Blogging gets you noticed
Blogging allows you to demonstrate not only your communication and written skills but it also helps demonstrate how well you can deal with technical issues and communicate how you solved them to a wider audience.
Ask yourself this, who would you prefer to hire, someone who's blog post you've just read or someone you've only just met. If the candidates were equal I know who I'd hire.
If you write a post about a topic, it's pretty much the next best thing to teaching it to someone else. Also, it's a point of reference. Your own personal Wiki. If you ever forget how you did something you can go back to it. There's also a great opportunity to engage others in your work and have it critique'd. Don't be afraid of putting yourself out there and opening yourself up to criticism, it'll make you stronger for it!
The more you write, the better you become at it. As with anything it's a fact of life that over time you'll improve any skills you practice at. We all sucked once (and possibly still suck) so don't shy away from writing simply because you feel it might not be as good as you'd like it to be. Concentrate on delivering with practise.
Potential Passive Income
There are plenty of examples of people who've made a pretty decent living from their blogs. Chris Spooner is a great example of one such person. He makes money from advertising, his mailing list, premium access members and affiliate sales. Imagine having that feeling that you didn't just have to rely on your paycheck to get by.
I highly recommend the email course by John Sonmez which walks you through how to get started with your own blog. On top of that he gives some really great tips on how to maximise your SEO and drive traffic to your site. Having top content though is an ideal place to start so if you do nothing else, at least ensure you have high quality content and copy (or as high quality as you can make it).
So what's stopping you blogging?
James Murphy runs the devangst.com blog which is a blog for helping developers cope with the daily stress and strain of programming life. Please feel free to subscribe to his RSS feed if you'd like to keep up with the latest posts.