How to get rid of spammy links and/or unwanted irrelevant links?

Is it possible to get visibility for on branded keywords present in the Google+ ?

Product page has insightful content of the product but the homepage and main product category page's also have the same content but in a short versions. Is there any possibility that Google is going to consider them as duplicate content?

So far we have done this. Rank for almost all main keywords in our blog's field. I am not saying the top position for all of them but most of them in our country.
Cleaned up all the link profile.
Do SEO for each and every product page. And also overall on-page SEO.
Actively participating and promoting in social media.
Guest post and market through forums to build authority.
Continuously build unique content and seek good backlinks from relevant pages.

Our conversions are so far good. We are making profit. But we want to increase it. What do your guys suggest?

Separate blogs in one site. I mean one blog for posts of mine only and another for guest posters. Is that a really good idea?

I am trying to get sales for my affiliate clickbank product. Surprisingly, after doing some research I found that linkedin is the place where why customers reside. What should I do? People keep saying that linkedin is a crapbox filled with spammy professionals.

How to become an expert in PPC? I have started learning it by running small campaigns in adwords.

Can anybody tell me which type of content specifically attract others to link to??

Many people have said me this that we have to part a forum into several amount of sub-forums when the main board has generate enough content. According to you guys when this should me good? I mean in the case of counting posts.

Why we should use Bing? I mean many people doesn't care but some of them specifically use Bing for some purposes and Google for the rest. What's the cause?