It's because they are kawaiiiiiiii! *sparkly eyes*

Yeah I noticed that too, dunno why really o.o

Genetics or different diets could be possible reasons.

If you're talking about real cats at least. xD I hadn't really noticed a difference myself.

I'd rule out genetics since it's consistent despite breed. I think it's the diet. A poor diet fades human eye color too after all.

Not one to cut in, I can't help it. Genetics make me go squee inside. About the consistency among species, they could all have developed simmilar traits due to their isolation from the rest of the world. Much in the same way Asian folks developed squintier eyes to aid them with the bright sunlight. Much in the way a certain breed of bird from the galapagos islands developed different beak structures to eat different nuts, those particular breed of cats may have developed brighter eyes to combat the harsh rays of the sun (Not certain however- somewhere I heard that the richer shade of color in the eyes, the better it is at deflecting light. I;ll research that later though)

Never rule out genetics. It's one half of the whole!

Though... diet... that could make sense too ;3;

Its japan man. Its where all the Glass eye effect came from! Rofl

US pet food is horrid. China is as bad or worse. I do not know much about Japan's pet food trade.

they have to keep their eyes open for sneaky chefs :P

Oh no, the diet speech again=P

It's the language barrier:
American Cats: "Meyow"
Japanese Cats: "Minya"

If you think about it, it all makes sense.

I think its more to do with the mass amounts of pollution in japan causing the felines eyes to become lighter

its an anime thing

It's cuz metric eyes have more candelas than Imperial ones.

I never really noticed, but I haven't seen that many Japanese cats to make a comparison.

Never really noticed a difference. Maybe your just visiting Japanese sites that take more photos of brighter eye cats then regular looking ones. Then again, I've heard that Japanese pets in general seem to be more calm and well behaved then ones in the US, so there might be little differences.

Do you have any photos with examples? =3

It's because JAPAN IS IN TROUBLE! #D

an excellent reference image :D