l33tness. If something or someone is l33t, it is/they are cool, skilled, neat, or otherwise nifty. Thus, l33tn355 is a measure of how l33t something or someone is.
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.