Well I've been playing almost daily (in case the user browser thingy works again search for Yeh_Ho_Di_Do IIRC you can see when the account was created in the history) till some months ago and it was down for me a quite some times, sceduled and unsceduled.
And even if I'll catch a lot of flack for this: it's quite possible that the copy protection of Tribes 2 killed the game for me (in a without it I would still play it way). The reason I stoped playing is that I don't want to join a tribe and prefer to play on publics. Sadly since quite some time it's not exactly easy to find a server with a decent ammount of people playing (Tribes 2 screams for big teams, not 4vs4 matches IMHO... and classic is crap
) and the ammount of people who play as a team vs the ammount of n00bs you find on publics became rather discouraging. Chances are, without the often not working logon copy protection there would be more people on publics and I doubt all of them would be n00bs.