It's true. The circle button changes his weapon loadout (either pistol, shotgun, or rocket launcher I believe) and then he has a different Level 1 for each loadout. The pistol is directly in front of him, the shotgun is directly in front and then at a 45 degree angle up, and then the rocket launcher is directly in front of him but across almost the whole map. And then he has one Level 2 and one Level 3, adding up to five supers total =]
No, I think I get it, finally. After looking through the trailer a bunch of times, it seems it's like this:
Rifle Loadout Level 1: Fast-moving, (possibly) mid-range projectile shot directly forward.
Rocket Launcher Loadout Level 1: (Possibly) Slow-moving, (possibly) long-rang projectile shot directly foward with a blast radius.
Shotgun Loadout Level 1: Two quick, yet very short range projectiles shot directly forward and upward at a 45 degree angle.
By my assumptions, Rifle L1 will be the safest one to rely on in a FFA battle due to it's speed and range.
Rocket Launcher L1 is capable of multiple kills due to it's blast radius and will probably have a longer range than the Rifle version, but will probably be slower to balance it out so that it's easier to dodge. It also seems to have a slightly longer start-up, but I could be wrong. Would best be used when the other opponents are bunched up.
Shotgun L1 would have more of an advantage in 1v1 or 2v2. It seems (again, could be wrong) to have a slightly shorter start-up time compared to the Rifle version. Which would give it more combo potential if I'm correct. It also has advantages over the other two versions given that not only does it shoot twice, but one of the shots go at an upward angle. This could go in hand with it's probable combo ability and will generally be good at catching elevated opponents off-guard. It also has potential for multiple kills, but that is not something I see happening very often.