Hi,
“Explaining why the new Mazda 6 should attract notice in the fiercely contested mid-size sedan segment, Mazda design director … believes the eyes have it.”
–Couldn’t find an explanation to satisfy me. Sounds like, “Its appearance speaks enough.” (If it’s not just a play on words explained by “The sedan’s headlamps were relieved and contoured by … to impart an eye-like visage that is more engaging…”)
You write:
[color=red]Sounds like, “Its appearance speaks enough.”
Yes - what we see with our eyes.
Now - let’s take a vote: do we approve of this new car and think it’s great, or not?
The ayes have it - it’s a great car.
[color=indigo]‘ayes’ pronounced as with ‘eyes’.
said to express assent; yes : “Aye, you’re right about that.”
• (in voting) I assent : "All in favour say, “aye.”
ORIGIN late 16th cent.: probably from I, first person personal pronoun, expressing assent.
The pun is between ‘eyes’ and ‘ayes’
As a matter of fact, I came across that one, Bazza, but it looked too complicated to me sending you back to as far as the 16th century. No modern guise of it? 
‘aye’ may have its origin back then, but is still in common usage today…
but that’s beside the point: in reading more of the actual article, I see (no pun here, even as far back as the 16th century):
[color=indigo]Any bit of differentiation helps.
Aye - this speaker really is just being mundane and talking about the headlights.
So - help me get up to speed on this:
We’ve gone as far as we can go in engine performance, passenger safety, comfort and emission levels. What now determines why I buy a particular car is… because I like the look of the headlights?
Over all our lives: superficiality rains! (bad pun intended).