The traits I described are typical of figures with parts manufactured in China. Those figs tend to be a bit less in quality compared to figs available in traditional sets. So far, those figs with Chinese parts (the arms with indentations and serial numbers, hands with serial numbers on the wrist) have been limited to the Collectible Minifigure series as well as certain "battle-pack" type figure sets released for original themes (
like this one). So, I'm happy to hear those traits aren't showing up yet in regular sets (with the exception of certain Toy Story and Superheroes sets).
It could be a variation in printing...maybe one fig had his face printed at a different facility...but that would still be a bit strange, given LEGO's attempts to standardize everything. Not sure what the deal is.