It's not in trouble of collapsing, there hasn't been anything worthwhile on the system since NSMB:Wii.
That may be the cause, but it's a matter of fact that the sales are collapsing. Keep in mind that it is sharply down compared to April 2009, which was following an even worse drought. The holiday titles of Animal Crossing and Wii Music had died off and in the following months there was what? Nothing.
It's also down sharply month to month, which along with other evidence implies that shortages were not a big issue.
A game I'm developing with some friends:
It is largely a technical exercise but feedback is appreciated.