This is my very first attempt at modelling a human head and also the first thing i've finished after studying maya... it's a subd head, done in about 45 min... please don't be too cruel 
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Looks good if its not human, but you stated that it's supposed to be human, so I'd have to say that it has some proportional issues. Do you have any referance, probably help you heaps. Keep a copy of it, could come in handy for an alien head.
http://www.eskiltomozydesign.comhttp://www.eskiltomozydesign.com
I agree with SurfaceSurfer, you need some form of reference (be it a photograph or book of anatomy) if it is going to be a human head. A few quick things: The eyes are rather far apart (centers of eyes should line up roughly with the corners of the mouth), the ears seem to be sliding off to the back of the roundish head, the jaw is a bit pointy and gets lost as it goes further back... amongst several other things.
In all, its not too bad for a first try (just a little wedge shaped/top-heavy). Most important piece of advice would be to use templates/references from pictures (like the front and side views), and then tweak it from there to give it the feel you want.
Trevor
is it my idea or the ears seem to be facing back? they are too far back anyway (at least he won't have any trouble being ambushed )
David
It's a nice model . Seems to be very stylized and does look alien.
If you want it to look more natural I would think that the eyes should be closer together and made smaller, the chin wider, the lower lip should have more weight to it and the ears need to be moved forward and smoothly connected. Also the neck seems to be way too narrow and does not merge with the jawline towards the back.
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Oh well, you are all right, and i appreciate all of the critics...but, the face here is supposed to be a lot manga style, and anyway it was done very quickly, because i just want to try how to have a right wireframe...thanx all
the face here is supposed to be a lot manga style
Okay then it seems appropriately styled. Although I still think the ears are oddly connected to the head.
Take a look at this link for some for some reference of manga esque females.
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WOWWW thanx for the link, it's awesome !!!!!
And yes, you're right again...the ears are just in "alpha" release...i need to find a better way to model them 