For it to have any sort of legal weight, a lawyer (or judge), witnesses, and both participants need to sign it. Also, it must be understood by both sides. Just signing it isn't enough.
My dad's a lawyer, and he knows this stuff. I'm probably leaving out some people, but that's the gyst of it.
Anyways, good form. You have too many broad clauses, though, for it to hold any weight. Such as
"hereby release (name(s)), and any other people officially connected with this event, from any and all liability for damage to or loss of personal property, sickness or injury from whatever source, legal entanglements, imprisonment, death, or loss of money, which might occur while participating in this event." No way that would hold up, ever. You are saying that a person could kill you during this event, and no legal action could be taken? Might want to modify that a bit.
Waivers are just scare tools designed to remind people to behave. Also, it sometimes keeps extremely frivolous suits out of court.