What's the difference between a VIP pass and a presale ticket to the Vans Warped Tour?

Can someone please explain the difference between them? I bought the presale tix already and I want to know if it was worth it. Then I found out there were VIP tickets. (it's my first year at Warped) Are the VIP tickets sold out? Is there a place to get them? What exactly do the VIP tickets include/guarantee? Help! xP