Few days ago I published some notes about my personal experience with PR 1.1.1 firmware upgrade in Nokia N900. In particular my device got an infinite reboot loop after upgrading the firmware and I had to flash the firmware image from scratch to fix the problem. Today I was kindly contacted by Max Waterman (I suppose he works for Nokia) and he explained me what was the problem. It was caused by a little bug in Harmattan UI demo and they fixed it (the fix is already available in extras-devel).
No surprise for me: extras-devel contains unstable packages and if user enables it, he does at his own risk. The most important thing is the fact that the official firmware without any unstable application doesn't suffer of this problem at all. The thing that really impressed me so much (in a positive sense) it's that I was contacted privately by a Nokia developer apologizing for the bug (no problem man, it's part of the game if someone want to test extras-devel software) and explaining that they already fixed it.
This is what I like of Maemo (or should I already call it MeeGo?), I really feel to be a part of it!