Hi Azazel,
Thank you for all the very nice feedback
Some commercial customers put Netduinos inside of their products...and some take our core designs and create custom boards. This is certainly something that you can do. We're here to empower you to create, royalty-free.
A few notes:
STM32F405 and STM32F407 are largely identical. STM32F407 has an integrated Ethernet PHY (also, the F415/F417 series adds integrated crypto). Finally, only STM32F405 is available in the smaller 64LQFP form factor.
Yes, you can flash the Netduino Go firmware to non-GoBus boards. You'll want to change the name of the board and USB VID/PID. You may also want to remove the GoBus hooks (and in fact we'll be providing a compile-time option for this in the future). There's also an alternative STM32F4 firmware available from our friends over at Oberon (see earlier posts in this thread).
Whatever you do, you'll want to get comfortable with the .NET MF source and become deeply intimate with the ST datasheets. There are quite a few specifics to these chips (like varying voltage and current tolerances, overlapping interrupts, alternate function and clock matching, etc.) that you'll figure out along the way. You'll want to build a validation board and triple-check everything before going into production. But the journey is with it.
If you choose to go the custom board route, please feel free to share your experiences with us in this thread.
Chris