Hi EggOfAwesome, welcome to this mostly dead but still lurked and patrolled forum.
Contrary to popular belief, Tremulous is not dead, nor has it been 'replaced' by any other thing.
1. There is very 'steep' learning curve. Each weapon, alien class and building duties for either team take a considerable amount of time to learn. This is not a FUNdamental problem, it just makes the game more complex and challenging. Tremulous feels much faster than NS2. If you've played any Quake* games the pace might feel familiar. Unfortunately there is no good tutorials nor documentation on how to play YET.
The best way to learn is to play with friendly folk who will forgive all of your rookie mistakes when you cause your team to lose.. Just kidding, just stick close to teammates (but not too close), don't attack friendly teammates or structures, and remember to slightly lead your targets that you're shooting at (aim slightly ahead-ish), and as a dretch remember to wall-walk to get outta the way of teammates and enemy fire, and to LOOK UP (way, way up) to get headshots on humans and you'll do just fine...
2. It is estimated that there are about 200-300 players in some sort of regular or semi-active state, but this number is low because there are many many more people who don't currently play - but still have good memories of Tremulous. FACT: Tremulous had over 100,000 downloads in its first year of 1.1 release (2006).
3. Yes. Tremulous has a high player-to-server ratio, so there should be a server near you with a decent ping. Generally servers might have 0 players, but if you join and wait a few minutes, other might join (especially if you invite people).
EggOfAwesome here's a shameless self-plug: We are formulating NEW STUFF for Tremulous at GrangerHub.com. The website for it is not up yet, but we do have some details on
http://forum.grangerhub.com To everyone reading this, please invite yourself over to our chat - the IRC channel is #grangerhub on the Freenode network (there's a web based client on our forums, at the bottom).
