I think the look of the game is dependent on both the programmer and the artist.  An artist can make beautiful, realistic looking models, but if the programmer doesn't write the shaders to correctly light the model it will be bland and unrealistic.  The programmer must also create the motions of various effects, blend transparent objects correctly, tweak the colors and intensities of various objects.  This leads me to think that the programmer has to have a just as good as a vision of what he wants as the artist.  Do you think graphics programmers should at least dabble with modeling and texturing or maybe even produce some of the content?  Or should that time be given to the artist, who can probably more effeciently create more content then the programmer?

Given the huge effort in creating a graphics engine I can't see the programmer actually being a content creator. While it might help to dabble, I don't think it needs to be a prerequisite.

A small team is usually divided into artists/designers and programmers. Sometimes you can have an inbetween position as the Technical Artist, an artist with some programming knowledge and deep knowledge of the 3D and 2D and not just be able to create goodlooking things.

Working this way it's really easy to expand the team...

Bigger teams (20 or more) might requier a more complexed structure. Then you have a Producer who manage the over all progress of the project. Below the producer you have the Leads and the technical dudes who manage their departments for an example a Lead Artist manage the Artists etc.

This is more or less the way all major studios work today.

 

   I count the basics of 3D programs(3dx max , xsi , ..etc) are essential for a programmer because he must apply some stuff to the objects before he can import it in his game, but i mean just the basics involving moving , exporting maybe texturing.

This is 100% going to be based on the individual.

• Some people are more programmers than artists ... in this case, I imagine it would certainly help to know your way around the 3d tools so that you are at least apt enough to create programmer art
• Some people are more artists than programmers ... these are the mages of max, the wizards of maya.  for these types, it helps to understand the constraints of whatever 3d engine they are using.  They need to be able to keep their artistic vision, while still meeting a polygon and texture size budget.
• Somewhere in the middle (as previously alluded to) is the dark art of the technical artist.  It is this rare breed that is at home both in the 3d and 2d art tools, as they are writing plugins for said tools, along with shaders, and even helping the engine programmers implement certain visual techniques.

It's not productive to try to shoehorn any one person into either of those 3 roles if that is not their strength.

Programmers that support artists need to have some artistic sensibility and knowledge. The role of the programmer is to translate artistic language to code. When the artist says "I want this to be shiny," it's up to the programmer to figure out how that translates to specular lighting, reflection maps, glow, etc. Typically, the programmer will have to ask more questions to understand what the artist means.

Similarly, for things like particle effects, it helps to understand how different artistic intents translate to code. Understanding color theory, blending etc is crucial. Having played around with layers in Photoshop is a great help, because then you have a common language to share with the artist. "It should work like the Dodge layer in Photoshop" is a fairly good description of some complex color blending operation.

Thus, you need to know enough to be able to communicate with the people who come up with your requirements, like in any other area of programming (or, indeed, development in general).

Well, when I got into the whole computer thing, the first thing I learned was HTML. I then got into Photoshop designing for the websites I was making, then CSS, then into PHP. Then I got into 3D Modelling (I love video games), then C++, then C#(XNA). Then DarkGDK (library for C++ designed for simple game design). I'm still learning C++/C#XNA, getting into HLSL programming.

I know:
    XHTML;
    CSS;
    CorelDRAW (Vector 2d program)
    Photoshop (Bitmap 2d program)
    3Ds Max (Still learning)
    C++ (Still learning, getting into some rather advanced concepts now)
    C#/XNA (Just got into it a few days ago, it's one steep curve.. should go learn Java, but too lazy)(Java is simular to C#)
    HLSL (BARELY getting the grasp of it, just started on that)
    Assembly (I understand the syntax, though I prefer High Level Languages like C++/PHP/C#)
    A few others, but you know what I mean :P.

Now, to answer your question: It would be smart to get into graphic design, even just for the basics, for a better understanding of what is going on and so you won't be dependant on someone else. I've learned EVERYTHING on my own. (Except 3Ds Max...)

A good site to help you: tutorialized.com. Of course, full of tutorials for many programs, like Photoshop. Even programming tutorials, and it's all free! (No, I am NOT advertising. just stating the best starting site :P)