atari looks pretty healthy to me.
It is not the same atari as we all knew and loved back in the day. I think they just use the name to sell games.
Also, I believe there is a group of dedicated fans who are maintaining, upgrading, and improving their Ataire ST's so I think Atari is about as demised as the Amiga is.
Plus, heard the argument that piracy killed off the Amiga too. But, since the Amiga isn't demised either we know that it isn't true. :-D
It all comes down to perception I guess. :-D