(Note: there are more Japanese sources with more stats, but I am not able to cover them all on this site.)
As you can see in the chart below, the Tokyo-based market research firm expects Japan’s social gaming industry to balloon to US$4.4 billion in 2012. Yano says that the growth will be fueled mainly by the rapid adoption of smartphones in Japan.
The numbers from Yano for both 2011 and 2012 are very close to what Morgan Stanley is projecting.
Here’s their chart again: