Is blog commenting still useful in search engine optimization while ranking a website?
No. All blog commenting tells Google is how much a website owner wants to promote his site – it says nothing about the quality or relevance of that site. Why should Google care about that?
But doesnt blog commenting comprise of user generated content that indicates ‘activity’ on the site?
I think maybe the OP is talking about commenting on blog posts in order to build links throughout the web. If I’m not mistaken, you might be talking about actual engagement on a blog which is in fact good (assuming its actual engagement and not spam).
Best,
Shawn
Right, I was talking about engagement… not about links 