How to social media strategy for B2B content based blog?

I am working on a B2B industry blog with niche topics on areas like ITES, Outsourcing, Software, Consulting industry. I am looking for crucial advise on social media strategy. Some of my questions are:

1. Observing the core business topics, should FB be considered for active social media presence? Any success stories or something to follow?

2. How should Linkedin be targeted? Since we are a blog but not a company, at least, not today, should we go for a group in Linkedin or still stick with a company page to push the updates to content?

3. Leveraging twitter - Looking for existing successful players,so far, I only found people with fewer then a thousand followers or those who are tweeting about everything but the topic.

Any other suggestions are welcome