kaedus29

While I don't condone the methods posted in this case study, I think that it goes to show that no-follow links do have value, that your on-page doesn't have to be perfect, and that the types of links that you claim don't work actually do.

http://serpfu.com/case-study-insurance/

Once again, let me clarify that I don't condone the type of link building here, but I don't think that you can argue that it doesn't work.

That link you posted seems to be 404'ing

Even if you have an innovative product with no existing demand, there are still blogs/communities that this strategy will work with. What is the more generic vertical that your product is in? In 4square's case, they could hit anything mobile based, social network based, or people doing geo-based mobile development.

I think this post focuses a little too much on the SEO aspect of this blog commenting strategy. While it is a good strategy for SEO, and it does work, I think the real benefit comes from becoming part of the community that is focused on whatever your startup is involved in. That exposure helps create customers/evangelists that will then help promote your product/service to others within their sphere of influence. The SEO is just an added benefit.