Forums signature, blog comment, but don't spam.
It depends on the google searches.
Page Rank is useless.
Analysis the buiding links of Competitors and study it.
It's the most effective. But don't spam.
Absolutely is google. I love it. It's my favor SE.
It's 15 - 30% I think.
It's very useful.
Facebook is best.
.info and .com .net .org is no difference.It depends on your seo work.
NO, I think it won't hurt your site.
The PR is not matter with Social Networking websites.
I'm using articlesbase, affsphere, fourpxarticles, snipsly, articlesnatch, goarticles, articlerich, articlestars, play-it-forward, ideamarketers,...
Google instant is not good for long tail keywords, but good for short keywords.
Separate names with a comma.