As a few others have experienced, my hardtop has a tendency to shed tiny dust particles from the headliner - especially when it is touched or pressed on... My kids thought it was funny until I banned them from the car if they did it one more time.
Anyway, it is the foam backing underneath deteriorating I believe. Only slightly annoying really but there nonetheless. Anyway, the other day I was blowing the driveway, and since the windows were down, I went in garage and aimed the blower at the headliner, thinking I would blow that stuff out once and for all...It was amazing how much just kept flying out. But here's the weird thing: I looked at the rear window as I was blowing and it was covered with the dust ON THE OUTSIDE! In other words, the dust was getting from the inside to the out from around the top of the rear window. Does this sound right -- should there be a seal or something. As far as I recall, the window has never leaked... Just thought it was strange.