I have 05 DG coupe and it isn't all the time I notice the ripples, or dots all over the windows except front windshield. It somewhat look like tire skid marks. I got it used with 1700 miles on it, so I didn't know if the first owner had really light tint or not. I took it to a local tint shop and explain to a guy who works there the dots...he looked at my car and said that there is no tint in it what so ever. He recommended to stop by the dealer and try to resolve this as a warrenty issue. I am not too sure how getting a tint will change the apearanace on windows-it could make it worse or make it disapear and not in game to toss couple hundred $ on that... Is this pro with most Gs? how's yours? Thanks in advance. BTW, I am dying to get some tint

 

You'll see wavy streaks and rainbow effects in the side and rear windows if you wear polarized sunglasses.

 

Are they the infamous "grease marks" some of us have experienced? There is a TSB for such, and your dealer should be able to fix it no worries.

Good luck!