Although most graphics are css based text in 4.0 (button set) the remainder of graphics (post icons, smilies, etc) that will indeed be graphic based should reside on one psd/source file, sliced, grouped so alterations, colour alterations, and saving be made in one easy step/click unlike in the vb3 series where the graphics were create in lightwave and imported to photoshop and could not be directly modified and each graphic saved out individually which became time consuming.
Constructing the icons/graphic using vectored implementation which would allow the images to be resized without the loss of quality, and colour alterations made and saved with a single click.
Just a suggestion, If this is the wrong area feel free to move.
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