Belushi81x is a minor contributor to DaibloWiki.
His real name is David. He is a Diablo Fanatic, having played Diablo II extensively, and Diablo I a little bit. Belushi frequently reads/posts on the Diablo III forums on battle.net under the name belushi81x, and occasional on the diii.net forums under the assumed name of BelushiEightyOneX.
He played WoW from shortly after release through the first expansion. He is known to have played most of the Final Fantasy series, Dragon Age, MUDs, UMoria/Rouge, Starcraft, Warcraft, Torchlight, Deathspank, Elder Scrolls, and many other games.
The rest of his, most likely uninteresting, back story remains a mystery.