a variation of the phase owned, the word is usually used by underaged kids playing online games like halo 2 and doom 3. the term owned is used to claim dominance over someone in some kind of situation, usually competitive. kids like using the phrase mostly because it's a taunt that they can use without getting their mouths washed out with soap by their parents. the phrase isn't very offensive to the recipient. merely annoying. the adding of 'zzle' is a product of people thinking that adding the "suffix" 'zzle' to words makes them somehow more cool and hip.
"yeah, i just got a triple kill!! you punks got owndizzled!"