Proper monitor calibration should be given top priority in anyone's workflow.  The issue you are seeing here are the differences between your own computers and those of others.  This especially noticable when you view the same image on PC and MAC.  PC's, printers, digital cameras and internet standards have been calibrated to apply Gc at approximately 2.2.  MAC's, on the other hand, are still calibrated at Gc=1.8 (native settings) which gives you a brighter images.  Beautiful to look at but potentially problematic when creating Web pages, printing or sharing images between computers.  But let us not ignore gamma correction totally.  It's application within a 3D program eliminates specific problems like too much lighting, specular blooms, incorrect colors, etc.  You either spend the time manually applying material corrections or invest in software (i.e., PoserPro or PoserPro 2010) which will handle Gc correctly.