Hi Raj,
You wrote 'Google says that if find that you're involved in any link building activities, we may penalize you' then every webmaster in the world should be worried.
There is a lot of fretting going on esp from people who have seen a decline in their SERPs. Don't believe all the hype.
I'm sure if you have the right content and bring value to the table, none of the Google updates will have an adverse effect on your site
