I just downloaded it today, and wow the problems. When ever I would plug in the iPod to the coputer it would freeze up iTunes and freeze up the OS. I will have to say this is the first time I have seen a Mac freeze. Right now I am working on going back to 4.7! My network load on my network is very high as iTunes 4.7 resorts the music coping form the network and writing back to the network. After that I will see if the iPod works again, and if it does I will back up the iTunes dir and test if I can delete the old files after consolidating the library. But for right now I have to want till iTunes finishes blasting my network.
Right now my Linux box is reporting about 2.3 Megabytes a second going over the network to its Ethernet card!! At this rate it should take about 3 hours to finish it.