No injuries have been reported, but Vitas have been burning out during recharging.
Japanese Vitas have been, reportedly, having a bit of trouble in the overheating department. According to a piece by Andriasang, 31 cases have been reported, 23 of which have taken place in Japan. In response, the Japanese government is looking into things.
The National Institute of Technology and Evaluation is looking into these reports, though Sony says that each of them has an explanation, such as liquids getting into the port while these consumers charged their systems. No injuries have occurred.