The LinkedIn profiles are mostly a Public Resume. Over 150 million professionals use LinkedIn to exchange information, ideas and oppurtunities. Most of the latest recruiters from companies are using LinkedIn to find employees.
And hence LinkedIn is especially important if you are seeking for a reputed job in a MNC's etc. Therefore it is important to keep your profile Updated and Active.
When you change or add your LinkedIn Profile it will be Instantly broadcasted to your each and every LinkedIn Networks.
This can become a great trouble if you are connected to your current employer or boss. If you would therefore not like your present employer to know that you are updating your LinkedIn Profile, you can block the Activity Broadcast by opening the Activity Broadcast and just uncheck the box.. (Finished now your Boss wont be knowing the news). Simple !!