Yeah, I've been working on it for 3 years, in the past year it's been able to support me. It's not a lot of money, but it's enough that I can subsist on it. It also doesn't eat my time 100% anymore, I can do some consulting on the side when I feel like it. I'm actually just traveling in south asia now, trying to live cheap and seeing if I can work from anywhere.
As far as SEO, I get some SEO traffic although most of it is to blog posts that aren't that related to web hosting. The most popular ones are about creating a reverse proxy/caching server with nginx and long running processes in php. web hosting review seo is super competitive and I'm nowhere near the front page for most terms unfortunately.
I have honest to god links, which actually still send traffic (amazing, right?). I also get some from social sources. I apparently get a bunch of direct traffic too... no idea where/why they are coming, but some days it's pretty good. Today's direct traffic is probably all HN.
