This is probably the most challenging prompts I’ve responded to. Blogging is a hobby I’ve grown to really enjoy, and while it has enriched my life I don’t think of it as anything beyond a hobby. So the notion of it being responsible for a life changing moment is kind of astonishing for me. Well if you have read my “about” page you will know I am an aspiring writer, so I gues a way my blog could improve my life is that hopefully it will already create an audience for my writing by the time I publish. Other than that, I really don’t know.
http://dailypost.wordpress.com/2013/07/12/daily-prompt-singular/
D.J. Garcia, Gentleman & Scholar 
As a fellow aspiring writer, the question of audience is a good one. Specifically, how one uses wordpress to reach out to a target audience. If one is writing a romance novel, the audience would of course be different than that of a science fiction story. Similarly, for non-fiction the audience would be different as well.
I am a fairly new blogger but the volume of posts under different tags I follow suggest that if you post book excerpts under #writing and the relevant genre say #fiction. Then also include tags relavant to your subject matter eq. Woodworking you should be able to get an audience going.
Of course, including appropriate social media links may further enhance your target community.
I agree that life changing may be a bit strongly worded but if blogging makes the difference between getting published or remaining an aspiring writer blogging may be at least life enhancing!