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So: If you want your links to be counted, put them in the post proper rather than in the comments.
Corollary: If your links aren't in the post proper then it means the blogger didn't feel your site was worth a mention. And if the blogger didn't feel your site was worth a mention, then your site probably isn't worth a mention. And if your site probably isn't worth a mention, then all your SEO attempts are, quite frankly, a losing battle to get users to a site which isn't even worth a mention from where they will promptly leave and go elsewhere.
Conclusion: Make a site of great interest and value and all the other things you crave will become much easier (apart from your sleep craving). Use comments to communicate with other bloggers and the wider community, aim for them to see your site and be moved to write a post about it.
My guess is that google will be looking more at the volume of traffic a site gets
It is frustrating having lots of links from the likes of StumbleUpon though that are all NOFOLLOW - I am not complaining about the steady stream of traffic they deliver, but I am lucky to be in a sector where that traffic is useful to me.
Getting mentions in blog posts is definitely what one needs to aim for in making the most of the social web for SEO purposes, sometimes you just need to be as blatent as to tell people that they want to blog about you!