PWNED is the internet equivalent to OWNED. As in "I owned you!"
PWONED - to be owned, or showed up by another. As an alternative spelling of powned, pwoned takes on a 'haxor' computer user overtone. Assumedly the creative spelling emulates a keyboarding mistake.
Most often used as an exclamation. Also used like " Here's the link to the file you said didn't exist, heh, you got pwoned!"