Back in 2003, Scott Miller from 3D Realms wrote some good comments on the implications of calling some games 'games':
"Who cares!!! Seriously, it's not like we need to work out the definition of the word "game" to make 'em! And frankly, I prefer to think of what we do as making "entertainment." Not that it matters, though."
It is a good point. Of course, on the other hand, defining things can help us see how to make it better and different the next time.