It's up to recruitment whether they think the blog is a valuable contribution. The blog by itself is not decisive but a blog along with a github in addition to your work experience and skills - that probably says something about you.
If you are the recruiter, you get to decide how much weight to put on a candidate's work experience, skills set, github and blog - it's your prerogative. There is no rule that says you as a recruiter MUST consider work experience, skills set, github and blog in your decision making. None whatsoever. You can do whatever you want.
My rule is that as a job seeker, your work experience, skills set, github and blog get you an interview. What gets you the job as a candidate is your performance at the interviews. Critical to your performance at your interviews is the insight that you have gained from your work experience, skills set, github and blog that you are able to share/communicate to those who are interviewing you. They are not hiring your work experience, skills set, github and blog. They are hiring YOU.
No matter how strong your quals are, don't ever walk into those interviews expecting that you're going to get something gift-wrapped and waiting for you to pick up.