My xB is a 2nd gen(2008).
I don't see it too often from other customers. I see it on the boards alot but if you notice, no one online ever talks about the good things. Bad news travels fast. Anything that breaks, travels accross the internet like a bullet.
the 1st gen xB's did see a few more rock chips then most cars because of the design of the a-pillars. The car is low to the ground and has a very upright windshield. It's not that it took more rocks then any other car, its the angle the rocks hit the window at. The glass seemed a little thin to me also but thats just an opinion and not based on any facts or specs.
the 2nd gen xB's have a little bit better glass but still have a somewhat steep angle of attack. Rocks Still hit the window a little closer to perpendicular then it would a camry or corolla but what are ya gonna do?
I've had broken windshields on my last couple cars. I don't see the xB being much worse and I can get a new windshield installed for less then 300 dollars if I get aftermarket glass. I really enjoy my car and everyone I've talked to that owns them is really happy with thier choice to buy.
I hope that has helped answer your questions.