Why wouldn't this thing just come with iTunes? Most of us would agree that iTunes is in need of a rewrite so why not just start with a touch based version? To me this should be a device that an iPhone can sync to and not a device that has to constantly sync to your Mac.
Since over 60% of Macs purchased are laptops, it would mean that most Mac users would be syncing their 10" tablet to their 13"-15" Macbook/Pro. It would look very odd.
Maybe, but this seems like an accessory device not your main PC so Apple will have to tackle the confusing dual iTunes Libraries issue. Surelydevicewon't capacity won't be so large ad to be able to handle most people's iTunes Library. I put a fraction of min on my 32GB iPhone and I'm fine with that.
I do see a place for a iTunes-like app that is a cross-between the read-only libraries we find on iDevices and iTunes on PCs but I think it will still be slaved to our master library.
Just because I think it will be an accesory device like all the iDevices doesn't mean I think it will require being plugged into a PC to sync. This is a different device type that isn't pocketable and possibly will be used in a general area or general way or most people. Perhaps Apple will allow OTA content syncing with this device. What makes since on a tablet any neccessarily going to make sense for a PMP or phone, and vice versa.