I'm happy to announce that a new book, Positive Psychology in SLA, has been published by Multilingual Matters. It is editied by Peter MacIntyre, Tammy Gregerson and Sarah Mercer.  
I have a chapter in it called "Happiness in ESL/EFL: Bringing positive psychology to the classroom.  Other chapter authors include Tim Murphey, Rebecca Oxford, Joseph Falout, Jean-Marc Dewaele and many others.  The editors also have chapters in the book.