Originally Posted by TommyLau
Another quick question, since I don't have the serial cable available, how I can know the Kindle Touch has succesfully booted into fastboot mode?
When a kindle in fastboot mode is plugged into your host PC USB port, you should see a USB device with VID/PID 0x1949/0xd0d0, indicating that the kindle is in fastboot mode.
You can also get the kindle fastboot tool and type (for the linux version):
sudo ./fastboot getvar bootmode
and it will show "<waiting for device>" until it sees a kindle in fastboot mode. When it sees one, it will run the command (getvar bootmode in this example) and exit.
Please do not use fastboot to erase or flash partitions on the kindle yet. The touch fastboot module seems to write to the wrong area, according to serial port status messages. There are other ways to do this that are more reliable at this time.