Gamma on the S is not as good, and blacks are not quite as good. Regardless of what people think they did last year, the S2 and G do not have a CMS control, and the color chart, as read with a meter, is more accurate on the G with THX, than you can get on the S. The reason I got the S, is because I wanted a 58", I then bought the DVDO to use it's CMS to get perfect colors on the chart.
S does 2:3 pulldown. If he's going to get a S, he should get the 58 or 65" and enjoy the extra size. The S looks good outta the box, calibrated with the Spears and Munsil disc.