Article about CENTRAL HETEROCHROMIA from Wikipedia:

Whereas Heterochromia (also known as a heterochromia iridis or heterochromia iridum) is an eye condition in which one iris is a different color from the other (complete heterochromia), Central Heterochromia is an eye condition in which there are two different colors in the same iris. Central Heterochromia is where the central (pupillary) zone of the iris is a different color than the mid-peripheral (ciliary) zone.
Eye color is determined primarily by the concentration and distribution of melanin pigment within the iris tissues, anything affecting those factors may result in a difference of color being observed.[...] The human iris can be seen in a number of various colors. There are three true colors in the eyes that determine the outward appearance; brown, yellow, and grey. How much of each color an individual has determines the appearance of his or her eye color.[...]
Eyes displaying Central Heterochromia are often referred to as "cat eyes" because of the appearance of a multi-colored iris. Central Heterochromia appears to be prevalent in irides containing low amounts of melanin.[...] Central Heterochromia does not label an eye as hazel. This is because the outer ring of an eye affected by Central Heterochromia is that iris's true color.

[http://en.wikipedia.org/wiki/Heterochromia#Central_heterochromia]

Article about HAZEL eyes (classification of color) from Wikipedia:

Hazel eyes are due to a combination of a Rayleigh scattering and a more than moderate amount of melanin in the iris' anterior border layer.[...]
Hazel eyes often appear to shift in color from a light brown to a medium golden-dark green. A number of studies using three-point scales have assigned "hazel" to be the medium-color between the lightest shade of blue and darkest shade of brown.[...] This can sometimes produce a multicolored iris, i.e., an eye that is light brown near the pupil and charcoal or amber/dark green on the outer part of the iris (and vice versa) when observed in sunlight. Hazel is commonly found in Europe, some regions of the Middle East, North America, parts of Central Asia and parts of South Asia.
Definitions of the eye color "hazel" vary: it is sometimes considered to be synonymous with light-brown and gold.[...]
In North America, "hazel" is often used to describe eyes that appear to change color.

[http://en.wikipedia.org/wiki/Eye_color#Classification_of_colors]

Here on Urban Dictionary you can find an interesting definition of "hazel eyes ": "Otherwise known as "mood eyes"

In the eye of Newzealander Barry Watson, the leading actor in "Boogeyman" (2004) capillary vessels and creature reflection are CGI... Yet his irises are not.

And 2 more stills from Jackson's "King Kong"; the ever-sad look (& looking) by Adrien Brody, Oscar for Polansky's "The pianist" (2000), reveals "our colour" in this (sad) enlargement

Kim Novak, main actress in Hitchcok's masterpiece Vertigo (1958); of that famous (re)transformation of Judy into Madelaine we can see here the revealing shot of her eye

Christian Bale, ultimate secret identity of Batman

Amy Winehouse, nicknamed "Wino", is a talented singer worldwide known for her amazing voice so as for her abuses of ...whatever. Beautiful eyes, anyway

This self-portrait with a ladybug, from the young photographer of promise Gordon McBride, a.k.a. =P0RG on DeviantArt shows the eyes colouring that he tells us caused by the effects of the Sunlight on his iris, which is usually brown... Strange, but valuable effect!

A 3DBeing here on YouTube shows how his eyes do not become lizard-like even when he's thinking about "lizerd" stuff... Could we accept this as evidence of his humanity? Of course, we like the round pupil when surrounded by those familiar colours.

Here's what I could say a perfect stranger:

Oliver Stone directed blockbusters such as "Platoon" and "Natural Born Killers"

A living comedy icon: Jerry Lewis -- As you may notice I don't like very much the modern photo portrating his "true colours"; but here's the link, just in case.

Robert Downey Jr. is now officially in our very special club; and yes, he's another Star

Believe it or not, even Insectosaurus from the movie "Monsters vs. Aliens" got it!

Popstar Rihanna (someone says they're Acuvue brand contacts =)

Image from the music video of "I know the trip" (album "Too many days without thinking" - 1997) by the Greatest Underrated Californian Band ever: SWELL

We don't mind whose eye -in which the camera dives zooming in the opening scene- is it but, again, its colours...

Showing also a beautiful case of heteroforia, along with our more "ambiguos" heterochromic feature, actress/singer Emma Roberts is the son of Eric and nephew of Julia (Roberts, of course)

Are classic blue eyes those of super-action-hero Bruce Willis? No, not exactly: we got the prove right here

In her online portfolio, Italian model Hedy Nerito shows us her beautiful look... and much more

I guess that Lake Bell is what they call hot stuff  in the US... Look at those eyes!

Here's Kristin Kreuk from the TV serial Smalville

Another special Scott is Emily, named "sexiest Australian woman"; I wonder why there are so few face shot of her on the web!

Harrison Ford. Da man.

Here on Picasa Web is one of the most beautiful living creature I've ever seen in my life; and it happens to have also the most beautiful eyes.
If human "hazel" eyes are called "cat's eyes" how should we call these?

Jennifer Connelly (with extremely light shades of different colors in her iris) starred at least in a couple of "cult movies" such as Dark City and Requiem for a dream ...
Not to mention Once Upon A Time in America, Labirinth, Phenomena, The Hot Spot ...
The Hulk ...

Alan Rickman often plays the bad guy in bad movies; but his eyes look good  enough to me

Al Pacino; he's an actor

This one is... well... mmhh... Niro... De Niro... Hey! It's Robert De Niro!
Now, I'm afraid we're running out of stars

Class 1999, Isa Briones is already a veteran in the show biz

Good ol' Bill Murray, oceanic hero of The aquatic life with Steve Zissou
(yes, he starred in Ghostbusters, too)

English actor Ralph Fiennes (The English Patient, Schindler's List...)
Perhaps his eyes are more blue-greyish-like than green-blueish-like but, definitively, heterochromatic

Rowan Atkinson is worlwide known as Mr. Bean. Such an intense look!

Tim Roth (Reservoir Dogs, Pulp Fiction)

Mr. Steven Spielberg is a professional movie director; I guess you already know him

NATIONAL GEOGRAPHIC

Read the complete article and watch the whole Hi-Res picture on The New World Encyclopedia