Some interesting research (you have to click through the article for the dissertation).

Using Crimson Hexagon (which is now part of Brandwatch) Pawel Bilinski who is Associate Professor (Reader) at CASS Business School in London has found out that:-

1. Companies using Twitter had higher earnings responses.

2. A higher number of Twitter and YouTube Posts leads to more positive price reaction. 

3. Social media communication is seen by investors as signaling a commitment to greater transparency.  Which will have an impact not just on earnings but to recruitment, diversity and inclusion and revenue (sales).

There might be something in this Twitter stuff?