Warhammer 40,000: Eternal Crusade at PAX Prime, I was given the opportunity to sit down and experience a PvP bout first-hand. I'll share a little pet peeve of mine before we get into the meat of the hands-on, which is that I really don't like it when developers stand over your shoulders at demos barking instructions to you. I wasn't given much of an opportunity to do what I wanted to; instead, I was constantly responding to the dev's commands!
In any case, for a pre-pre-alpha build, I'm somewhat impressed that Eternal Crusade was able to cobble together a very playable deathmatch with several classes and two vehicle types (Rhino and Predator). My first class was something of a lumbering tank, well-armed but a clunky jumper. I opted instead to get a jetpack as an assault trooper, willingly trading firepower for the awesome ability to do huge leaps and be able to clutch on to the side of a building and jump once more.