I realize it's a C5 forum that started it, but it's funny to me how much they all talk about how beautiful the C5 is. That's my least favorite generation by far, looks like a bloated, melted soap bar with the biggest *** on the planet. Which means exactly zilch, everyone has their own standards of what looks good, which is why these kinds of polls are useless except for generating debate.
I'm a child of the 80s and when I saw my first C4 in late 1983 it looked like a spaceship, just fell in love with it. It's the simplest, cleanest design of all the generations and I still love it. And I agree the extra width on the ZR-1 makes a huge difference.
My styling favorite is probably the early C3, specifically a '69. Awesome looking car, but holy hell they drive like trucks. Just terrible. I wouldn't own one for just that reason, but it's sure cool to look at. I even think the late C3s are cool in an 80s kind of way, but wow they need some power under the hood.
After that, probably a tie between the C4 and C7 (love the wretched excess style). Then the C6, followed by the C1 and C2, and then the C5 dragging its big ol' *** up the rear.
Sacrilege alert...I don't really like the C2 either, but it's marginally better than the C5. There you go, proof that styling polls are useless.