We have some good news in Arduino side. They came up with two new and different Arduino boards – Arduino Uno and Mega2560. These new Arduino boards are somewhat different from those that we are used to see. And probably biggest changes are different approach in converting USB to serial and different bootloader. First of all USB chip… They decided to get rid of FTDI chip (FT232RL) and used Atmega8u2 chip instead that gives even more power when dealing with USB. By default chip is configured to work as USB to serial converter, but there is an option to turn Arduino into different USB device like mouse, keyboard or MIDI device. So these are good news. Bad news are that using atmega8u2 forces to have your own unique product ID and vendor ID – these cost money, while FTDi chips came with their IDs. But this is more important if you want to build your own board – many of them. Anyway there is always an option to get back to FTDI as bootloader doesn’t care how data reaches it.
Next improvement is bootloader itself. They started to use different bootloader – Optiboot. It works with same STK500 protocol and uses 1.5K less code – so more space for custom programs. It’ even faster! Good news is that finally they added separate 3.3V supply that gives up to 150mA instead 50mA that came from FTDI internals.
And finally both boards are pin compatible to all existing shields. Uno board still uses ATmega328P, but if you need more horsepower then chose Arduino Mega2560 that gives more memory and more I/O pins. You can find great review on these new Arduino boards in laylada. This is a great kick forward for Arduino community.