Product Marketing and Advertising Online: Open the Door
Much has been made about the value of the two-way communication model of online marketing. People have minds of their own, and the sheer weight of options available on the web means that most people have an easy time ignoring companies they aren't enjoying communicating with while going on to find a competitor's product.
Part of this ease of communication is making it one-click-simple for users to get into the communication network of people they're interested in. The principle of including a call to action is already well established in marketing circles; don't just present the case, invite people to make a decision (buying, subscribing) related to it. The same can be done with a well-considered opt-in strategy for any of a businesses' online marketing ventures.
Adding opt-in steps is an easy online advertising trick. For example, consider a brand blog that lets customers know about all the developments going on in a new product's release cycle. Each blog post should be linked to on Facebook, and the blog itself should have thumbnail buttons allowing people to like the article on Facebook and even follow the blog's author. Similarly, e-mail newsletters and advertisements should always have assorted social marketing buttons that allow for easy following. They can even be put into a simple all-in-one button that connects a user to each account for quick access.
This process works because getting involved in the online community is only half the step to good online product marketing. Yes, you want to get involved and speak to people about common interests and build up good credibility. On the other hand, there is still value in putting yourself and your product out there, and giving people an easy, automatic way they can keep informed if they so choose.