I too, bought a 15 powerbook on the first day they were released (serial number W8540). I am now quite certain that it did not have any of the display issues. It did, however, have problems with dropping airport connections and I made the mistake of having it replaced by Apple. The new PB ( W8544) still has the airport problems and you guessed it (also, both of the bottom corners of the display are black on this PB). I called Apple in early Dec. about this and the second level tech support guy said that he had seen the
http://crankycat.com/pb15_problems.png image and that the engineers are working on it. He also said that he would contact me in 3-4 days. It had been almost 2 weeks and I had not heard anything. I called tech support again and talked to someone else in tier 2 support, this guy said that he could setup a replacement but it was likely that the new PB would be any different and to call back Jan. Called back talked yet another tier 2 support guy (this guy was a bit of a jerk) he said that they could repair the PB. I decided that I could not trust this guy (if one the first two guys had told me this, I would have believed it) and told him that I was not convinced that the problem would be fixed. He told me that this was what Apple was prepared to do at this point and that he was now taking over the case and that I would deal with him exclusively from this point forward. The next day I called Apple customer service in Canada and told them that this was my second DOA PB and that I have been with Apple since my first SE and was very disappointed and wanted to return the PB. The customer service person said that she was sorry to hear this and gave me a full refund (after I return it of course). I have now ordered a MacBook.