Recently, I have seen a lot of articles on the effectiveness of Twitter, how people are using Twitter, and what they are tweeting.  Some of the articles are interesting and thought provoking.  But, I think that measuring a direct ROI is missing the point.  Twitter is about building relationships, first and foremost.  So, you won’t always see a direct correlation between what you tweet and sales, it is a gray area.  What you do benefit from is building your brand and your reputation.  You prove that you are knowledgeable in your industry, that your company is willing to listen and provide help, and that you care about your customers.  Whether this results in immediate sales or not, it will pay off in the long run.  And whether or not  Twitter is just a fad, the idea behind sharing not selling, and building relationships is not going away.  There just maybe a different tool in the future.  For now, that tool is twitter.  So stop worrying about what you are getting and start participating.  Only then will you see results.