He is certainly an appropriate choice given the Templeton Prize criteria, and the press release gives a nice description of his work related to religion, but I was surprised by this claim:

Alvin Plantinga, an American scholar whose rigorous writings over a half century have made theism – the belief in a divine reality or god – a serious option within academic philosophy.

As I noted years ago (reported in no less disreputable a rag than the NYT), Christian philosophy is a growth field, due to the increasing number of Christian and religious people in the community from which philosophers come.  And Plantinga certainly gave them dialectical cover for professing their religious belief, and many of them are extremely good professional philosophers.  But the vast majority of philosophers are atheists, since supernatural beings don't exist, and Plantinga's attempt to rationalize religious belief has had, as best I can tell, no impact at all on those outside the relevant sectarian groups of religious believers.  

Given the Templeton Prize's mission, Plantinga is an excellent choice, and perhaps in future years they will also recognize Robert M. Adams, another distinguished Christian philosopher.   But no one outside philosophy should think that the work of these dialectically clever and acute philosophers has actually had any effect on the consensus view among philosophers, and post-Enlightenment folk generally, that God still does not exist.  Of course, consensus is no proof of anything, but here at least it is rather clearly truth-tracking!