Khoi Vihn, in an interview on Own Your Content:
It’s hard to overstate how important my blog has been, but if I were to try to distill it down into one word, it would be: “amplifier.” Writing in general and the blog in particular has amplified everything that I’ve done in my career, effectively broadcasting my career in ways that just wouldn’t have happened otherwise.
Same for me. Nearly every opportunity I've ever had has come as a result of my blog. I know this sounds like hyperbole but it isn't. Yes Twitter helped (when I had an early account with thousands of followers, etc). Yes going to events all over the world helped. But it all came back to my blog.
Also, my blog has helped me to form, confirm, or reject my own ideas and hypothesis. I cannot even count the number of times I've started a blog post (read: rant) on a particular topic only to completely change my stance on it by the time I was done writing. Writing is how I think and I write on my blog.