Glad you posted, since you could never know I had seen it!
The interface is totally different than the original iPod firmware, so I need some time to get used to it.
Rockbox is not mature enough for me yet, but I'll certainly follow the development.
Some griefs:
* Almost impossible to load the original firmware (5 of 6 tries fail).
* Rockbox crash if its not loaded when I plug in the USB.
* Power consumption.
* Dont remember playback point after sleep.
* No HFS+ support (I know I'm asking too much).
* No battery meter.
But Rockbox have only been running on iPod the last 3-4 weeks, so I am certain it will be better in the recent future.