So Tribes: Ascend recently went into open beta, and I've been screwing around a bit on that recently.
If you're like me and never played a Tribes game before, then what you're in for is a fairly solid class based FPS that is largely differentiated from the crowd by the extreme mobility. In Tribes, if you're walking somewhere then you're a target. You are constantly using a combination of your jetpack and skiing to both reach destinations and evade fire. If you've ever surfed in a Half Life based game, then it's a little like that.
I like the style, though I have a fair enough amount of experience with FPS games that I was able to play competently from the beginning. It's a requirement to be able to lead people with rockets or use an assault rifle against people flying through the air. BAsic movement requires udnerstanding the physics of skiing and energy (jetpack fuel) management.
The gameplay feels solid and doesn't have any elements I find disagreeably yet. When I die, I feel that it's because of my mistakes, and when I kill someone it's because I earned. Death match even has an interesting tweak on the old concept, as there is a flag that can be held giving double points to a team. This creates an objective in the midst of mindless slaughter that does help mix things up quite a bit.
Everything I dislike is in the backend. There is an unnecessary leveling up system in which you can buy a few sidegrades, but mostly you're upgrading your class to simply be better. This feeds into their free to play system where you can purchase upgrades more quickly with the use of real money. Additionally their graphical and sound options are incredibly limited, as if the game was designed for console and ported to pc.