Is it "playing the age card" if McCain is actually too old to be president?

There seems to be an unexplored aspect to this media debate as to whether Obama is "playing the age card" against McCain. Namely, maybe McCain is too old, has been acting confused, and thus it's not a card.

We need to stop pretending that age is the same thing as gender or race or whatever. It's not. When you're 90 years old, for example, you're not fit to be president of the United States. When you're black, or a woman, you are - or at least your race and gender have no impact on your job performance. It's all well and good to be polite little PCers and pretend that it's age-ist to talk about McCain's mental and physical health, but anyone who has ever had a family member in their 70s knows that they start to show some wear and tear in that decade. Hell, I'm starting to feel some wear and tear in my decade. We've all seen the photos of how a president ages so much in office. And we all remember how out of it Reagan was by the end of his second term. Your age is an indicator of your health, and once you hit your 70s, I'm sorry, but it's a fair question to ask if you still have what it takes to be president of the United States of America.

Not to mention, McCain has been confused. Very confused. So whether or not the "age question" is nice, facts are facts. McCain isn't all there of late. And he's certainly less there than he was when he ran for president 8 years ago. Perhaps he's always been a bit confused, and we never noticed. Perhaps. But let's stop pretending that his age isn't relevant, and that it's wrong to even ask the question.