The iPod Nano is not compatiple with Firewire. When I plaugged mine in to my Mac at home, I was presented with an error message that I could charge the iPod, but I could not transfer data. It took a lot loinger to upload my music using USB.
Other than that, I must admit, I realy love the color screen. It syncs all of my contacts and photos very nicely. This is also very good integration with the enhanced podcast. It is like having chapters that you can page through using the next song buttons. It will also display the different artwork for those chapters.
The battery life is phenominal. I used my iPod Nano all weekend long with out recharging. According to Apple it has a 14 hour battery life. It only takes one and half hours to get an 80 percent charge. So far I am extremely impressed.