These graphs, from a larger paper done by Mike Zuurman of Xentax, show a dramatic decrease in the number of games released since 2009. As the author notes, this may be due to decreased reporting by gamers (entries at MG are user-generated), because it doesn’t seem to square that the real number of games would plummet at the same time that the casual market has exploded. Still, worth a look and a longer read.