1.You swap between your weapson using Y or Triangle like most shooters. Works great to switch to your heavy weapon just hold the weapon swap button. (its limited ammo anyways comes in handy in ambushes and boss fights) 2. The skill try gains experience everytime you fight in the alpha you couldn't go so far because clearly it was an alpha. but weapson also carry skill trees (ability) that you can level up the more you use that gun. Some guns didn't have it. 3. Im not sure didn't really play too much with it was too busy killing guys and exploring (highly addictive game) 4. Item Weight I believe we will see in the beta I never tried filling it in the alpha because I kept breaking down useless stuff for glimmer 5. All enemies drop stuff but from what ive seen so far mainly the epic boss battles drop rare guns and armor. Im not sure about the raids or public events for I only came across two public events and never a raid. Overall the game is highly addictive, Serious potential and I understand why bungie also doesn't offer trading to other players because they want you to experience the fights for yourself. the Multiplayer is brilliant and well balanced and aggressive mostly because there are so many ways to enter a capture point so the element of surprise is there. In the alpha with the little bit I got to see I was never bored. I always found something new to explore or a mission on field to complete and each class has a different style for different players