Just starting out -- basic questions

I recently ordered an HP Jornada 720 with dock that is scheduled to 
arrive soon. I have a few questions about running NetBSD on it.

1. I understand that I need some form of storage -- usually compact 
flash -- is there any maximum limit for size? Would 4 GB work?

2. Do I need a serial cable to boot it, or only for debugging? Is this 
the kind of cable I need: http://tinyurl.com/227ljw

3. How is battery life while running NetBSD?

Thank you for your time.

-Alex Hanson