Today I had to transfer a lot of DVCPRO HD footage from a Panasonic AG-HPX170 camera. I discovered that the USB 2.0 port transferred easily twice as fast, if not faster, as the 1394 FireWire port, when connected to a Macbook Pro. This was a surprising result! I suppose the FireWire port is more useful for direct video capture and monitoring than it is for transferring video from the P2 media cards. Adobe OnLocation plus a laptop with a high-resolution screen makes for a great field monitor, with scopes and annotation tools included!
And praise to Panasonic for releasing an update to P2CMS that now works with Snow Leopard!