With social media becoming an evermore important part of the way we search for careers and our lives in general should we actually change who we are when we are online? In my opinion, this isn't necessary although I do think that being able to communicate your own personality over a variety of media takes time. So how do you actually achieve success in using social media? Be. Yourself.
If you are normally fairly chatty and friendly, that should come across in your posts/blogs/conversations. That is not to say that you can't challenge yourself; I found that using Twitter really enables me to think about the importance of what I want to say.
As the article says, you need to be consistent. Whether you are using social media for your personal life or your business your personality should shine through. Of course you will need to change the language or the content depending on your audience (that too is important) but underlying all of that should be you.
Your personality forms part of your 'brand' your 'USP' and if you are predominantly dealing with people over the web there isn't much else to go on. If you use social media a lot, you will find, eventually, that subconsiously your personality comes across naturally and hopefully this will build your credibility, your brand and your success.
So, what do you want to be known for?