From a user point of view, booting a N9 has the following steps :
1) show animation
2) a little beep since PR_1.1
3) animation goes on
4) nokia tune
5) enter pin code
6) booted

First I have a question: I did not have step 2 initially. What does it mean ?

Second question: does anyone have insight about what really happens under the cover ? At least it must be checking for a flasher software on the usb, I guess. But there must be a ton of things happening... Any pointer ?