I'd care because it shows that the candidate cares about their craft to the point that they are trying to share their opinions with others. Granted, the vast majority of people in the world don't blog, so in my mind its only a "plus", but being able to read someone's written thoughts does give you extra-credit insight into their way of practicing their art (given the blog is on topic, of course).
But surely you get credit based on what you write, not just for writing it?
There are some pretty bad blogs out there and, IMHO at least, it wouldn't take much to write something which was worse than not writing at all. Caring about your craft is good but whether they're actually good at their craft is best judged by the content of what they are posting rather than it's mere existence.
To me, a candidate who has a tech-oriented blog (and has maintained it for some time) gets a big bonus. One who has a GOOD tech-oriented blog is a whole other story -- that puts you in the category of people who can skip the normal evaluation process. But GOOD blogs are rare enough that I've never seen this come up. Even poor blogs are a very good sign.
I guess I wasn't explicit enough with this bit of my comment: "give you extra-credit insight into their way of practicing their art". Certainly simply having a blog and spouting drivel doesn't benefit a candidate, but I sort of expected that to be understood.
idk I think it can mean that they're egotistical, stuck in their ways, believe their way is the only way to do things etc. (For example 37 signals type blogs)
It can also mean they'd rather write blogs than code.
Obviously it depends, but I don't think having a blog is necessarily a bonus and could well be a negative.
Well that's easy. It's because the writer of the table has a blog, and therefore people who have blogs are obviously superior to those who don't.
I'm gonna assume that this "programmer competency matrix" is a "How similar are you to me?" matrix. Skill sets which the table author lacks are missing entirely, and for other skill sets the precise skill level which the author happens to have is the highest possible level.
If you are trying to hire someone and you have multiple candidates you may need a differentiator. If someone has a good programming blog that's probably:
a) another way you can assess their programming knowledge
b) a net benefit for your company's PR
c) an indication they will help others learn
"Has heard of them but never got the time."
"Maintains a blog in which personal insights and thoughts on programming are shared"
Why do I care if someone writes a blog or not?