Depends on: niche vs competition vs SEO vs uniqueness of content vs relevance of content... But looking at serp's right now even if you just blast a spammy blog you'll be fine.
What a daft thing to say. You've no idea where he's been placing his links, that's just an uninformed guess.
it depends on which places have links back to your site. For example i place links on pagerank 5 sites etc and normally get credited with those links quite quickly. The higher the Pr of the linking site, the faster the link to your site will get indexed and counted.
if ur site is new and you are looking to get quick traffic and indexing you can read at How to get quick traffic to new site?