Return on investment for social media

ZD Net recently looked at the return on investment when it comes to social media. They believe that social media will return your investment if you put the proper amount of time into it. They also point out that if you have the proper amount of social media, you can avoid social media disasters. ZD Net cites the most recent social media disaster for United Airlines, United Breaks Guitars.

Do you believe it's worth investing in social media? As we've seen with many companies, United not the first, many PR disasters come about due to social media. Should companies have measures in place to control these events?