Realizing there are multiple factors in play when it comes to effective hosting...for each connected player (firewalls/handshakes/etc)...
What would be the minimum threshold upload rate that one should hope to see -- in order to even consider themselves as a potential lag-free host?
My basic tests show around 4-5 Mbps overall...but I don't know how solid my XBOX nic capabilities are. It's within 15 feet of the router so it can't be too bad.
That's an interesting question...
Considering that all XBOX players are using common hardware, there's really only network latency to account for. A measurement of latency to the host should characterize the entirety of the network infrastrcuture (firewall, etc.). It would be best if the packets used to test latency used the same ports as the application. Firewalls either permit or block, and should not be a huge factor in determining latency (unless seriously misconfigured, or overloaded), an IPS might be another issue however,
The upload and the DL are both important as the hosts are constantly updating with the server. I can't say I really have any any understanding how this particular game works, but what game wouldn't be better served by at least allowing for network statistics for hosts to be presented?
cough*Battlefield*cough