Bought my truck in Jan. 04, all of a sudden im getting traces of grease on my front drivers and passenger windows (from rolling and unrolling )
Only thing that gets it off is a special adhesive remover purchased at home depot.
Certainly not the end of the world, but is somewhat of a pain in the ole ****.
Just thought it was odd that it would start after all this time.

 

anaheim- I had the same problem with my truck shortly after buying it last September. At first, I thought it was some adhesive from the window sticker that had worked its way down inside the door. I'd clean it (like you said......a pain in the rear) and it would reappear. Clean it..........reappear etc. etc. Finally I brought it to the dealership. They supposedly fixed it but it reappeared again within two days of the "fix". Took it back again, and this time they got it right. I neglected to ask for details of what they did to take care of it, but I haven't had a problem since November when it was done for the second time. I didn't notice where you lived (anaheim CA maybe?), but if it's in the colder parts of the country, maybe it starting showing up now because of the warmer weather (the grease is getting less viscous and flowing more easily) and/or you're opening and closing your windows more now that it's warmer.

 

It doesn't get cold in Anaheim, but as you mentioned, it is defineatly warmer than it was in January.
Well, i will try cleaning it one more time, and if it re-appears, guess im off to the dealer.