I've played devil's advocate and come up with some instances in which you may not want or need a blog for business. But for the most part, blogging is good for business - any kind of business.
Interestingly, GoDaddy has a lot of good stuff to say about blogging. I say interesting because GoDaddy isn't really big in supporting its users with blogging tools. Go figure.
Anyway, blogging is good for business. Seriously. See what GoDaddy says about it here:
Here's another perspective on how blogging augments your PR efforts, too:
Need help starting or updating your blog?
I can do that.
7/7/17 UPDATE: Yet another article with some good advice on making your blog more productive, from Mark Shaefer's Businesses Grow.