In your opinion what type of blog comments are better see the two examples. A) 1,000 backlinks all from 20 sites 50 links per site. B) 1,000 backlinks from differnet blogs only 1 link per blog. Which type of links do you believe to be more effective in the long run?
B) for obvious reasons . Its better to have more sites linking to your site, than several, it makes the links more... real... But if you have site about fishing, and have 1000 links from 1000 sites, that have niches absolutely different in every way than fishing their strength will be closer to 0. If the 20 sites(50 links each) are related to fishing(or your niche, whatsoever) their strength will be immense. their strength will be more than the strength of 10 000 links from links from other niches.
As lifeplayer says it probably depends on the quality of the sites, all things equal I believe B would be better however it would be hard to find 1000 relevant blogs to your topic so going with option A could be more effective if the sites are more targeted.
I disagree (depending on niche ofcourse) if you have a blog about Loans then I'm sure there's millions of blogs.
Normally one site should only need one link to you, otherwise it would be redundant wouldn't it? Then again who decide whats normal these days
I feel it is all hypothetical discussion going on . Nobody really knows what sort of calculation is done by google .
I believe that A is a lot better than B, and it's because to me relationships is what matters the most when it comes to marketing. If you comment on a few blogs, the author will know you, and the readers will recognize your name. Within a few months you might have a great following (a tribe) because of all of your quality comments. With option B, all you will have are all the backlinks (they matter as SEO, but that's all).
Of course, SEO is just a lot of hypotesis and a bit of BS, I don't think even matt cutts understand it fully