I tried it out last night, its a lot of fun if you can get over the delayed response to your key presses. The reason for the awkward steering is because of how the Source engine handles vehicles in MP (I don't entirely understand the problem though). Anyways, there are two manually controlled weapons (MG and Mortar) and two auto lock on weapons (Minigun and Missiles), along with three vehicles. All have their purpose and require different tactics.
The basic twin MG everyone starts with is weaker than simply ramming another vehicle, it basically exists in order to avoid being completely defenseless. And on the hedgehog I think it was, you couldn't fire behind you, might be all vehicles. The twin Miniguns is a step up from the starting MG but you can only fire in front of you and it auto-aims for you. Though it works adequately, sometimes I feel as if I would be a much better shot than the auto-aim, especially around hilly areas (it hits the ground a lot in that situation). Next up are missiles, when you pick them up, right clicking chooses a different type. Red missiles, represented as an icon with three missiles and a straight line, are the most powerful, but have a weak lock on and are the least agile. Orange missiles are represented by an icon with two missiles on it and a semi squiggly line, these are middle of the road in lock on ability, damage, agility. Lastly, Purple missiles, are, you guessed it, the weakest with the the strongest lock on ability and agility, I'm sure you can guess what its icon is. The only way to avoid being hit is insane maneuvers (which will mostly work for orange and red missiles and rarely for purple) or launching a counter measure. While counter measures do work, you can fire 3-4 missiles before it reloads, so you either have to kill your opponent or drive like a madman to stay alive against a someone with a lot of missiles. However sometimes neither can save you, especially when your in a wide open area or you happen to unlucky enough to be near your countermeasure when a missile strikes it and be blown up (happened to me several times
).
Now for the last manually aimed weapon, the mortar. IMO its projectile is way too slow to be useful even at medium distance, as it suggested to be used at. On top of that, the crosshair is hard to see on the ground, especially at high speeds with constantly changing scenery. So to actually hit anything with it, you have to either be really far away from the action, or be shooting a stationary targets. And even then it will hit or miss because of the combination of slow travel time with hard to see crosshair.
The vehicles, for now, are the standard, one has high HP with low acceleration and handling, one is middle of the road, and one has low HP with the best handling and acceleration. They may feel ordinary but at least they look cool.
Though all these problems are forgivable for a first release. Especially since the Source engine is fighting against you sometimes ("I swear I was clear of that corner when I was making that turn!"). I can't wait till next patch
.