"Centennial" implies something that has been around a while. In the US, Hyundai is just too new to try to pull off this type of name. Most US buyers probably think of Hyundai Automotive as less than 10 years old: "Hyundai's centennial? Maybe 100 months... certainly not 100 years!"
"Equus" doesn't translate/mean anything to most folks; it'll be a goofy word just like Toyota using non-words Camry, Corolla, etc. It certainly meant nothing to me when I first saw it... and I still don't know what the correct pronunciation is. Imagine the car magazine and newspaper stories announcing the "new Hyundai division: Equus" and then having to spend the first 2 or 3 paragraphs explaining what "Equus" means... by then half the readers will have lost interest before they even read about the cars.
"Genesis" is a word that needs no translation. Folks won't get distracted thinking "what's that supposed to mean?" (like they might with Equus) and thus will be able to pay attention to the products!
Honda went with "Acura" which sort-of sounds like "accurate" - and then they made a logo based on precision engineering dividers to reinforce that idea and based their early advertising on those ideas too. "Lexus" is another meaningless word (to most US folks) but it sounds high-zoot and there is no question on how to pronounce it. Nissan's "Infinity" name is a well-known word just like Genesis would be yet "Infinity" has certain "big, forever" connotations.
Ideas of my own? Haha... I can critique forever but I generally can't offer better suggestions. Some word that is a fancy-sounding synonym for "surprise" or "astonish" or "astound" since that's what Hyundai is doing to the auto industry in general. In fact, my name for my Genesis sedan is "Surprise" for two reasons: 1) that it IS a Hyundai and is such a surprise home-run car from them, and 2) that I actually bought (and like) a 4-door sedan with an auto tranny. Folks that know me were surprised by that; everything else I have is a 2-door coupe/hatchback with stick-shift. ALL are rear-
wheel-drive; that's one thing I won't give up without a fight! Anyway, too bad some form of "astonish" is too close to the existing "Aston" in "Aston-Martin." (i.e. twist "astonish" into a name just like Honda twisted "accurate" to get "Acura") What can we do with "astound?"
my opinions anyway. Obviously I voted "Genesis."
mike c.