I can understand wanting as many options open as possible, and it would be nice to see IP over FireWire, but I don't think 10.1 has it--at least, I haven't heard so much as a peep about it, so I figure it's not likely included at this point.
Then again, I'll chime in with the "not necessary" crowd and point out that, if you're really doing networking, your chances of finding a client that doesn't have an Ethernet port but does have a 1394 one are pretty slim.
The one time FW networking would be nice is for quick, easy file transfer... and in that case, you don't really need IP. Since, as far as I know, FireWire disk mode should work under 10.1 (or 10.0 for that matter), you've got a decent chunk of the reason for simple networking even without FW-IP.