I got a pair of Polished Black/Ice Gascans, and they are the new generation (logo on earstem, inside nosebridge has a dimple) and I compared them to my two other '1st gen' gascans, and the earstems on the ice pair curve in more, giving a tighter grip.
I also assume the dimple in the nosebridge was Oakley trying to get rid of some weight on the front so the glasses have less of a chance of sliding off when you lean forward.
I don't know if the new generation was made to fix the fit problems of the inital run, but judging from this one pair they have made a good difference. These new ones wrap my head better and don't slide off my face as much.
Oh yeah, the Ice lenses and blue icons look SICK!