I guess the real question is, *which* are we celebrating? The advent of Linux as an idea? Or Linux as a reasonably stable, proud-to-be-here OS?
Honestly, though, I think the whole thing's just silly. For example, Linus has *always* released "dot-oh" releases when he was felt it was damn-well ready. Not so much for most commercial packages, though; they're marketing driven. (I think we need look no further than Vista to prove that.) While I'll be the last to say that Linux is free of politics, it is refreshing to have a beneficent dictator who usually makes the right choices. And his choice to release 1.0 about when he released it was a good one... and worthy of being commemorated. Attempting to "disown" the commercial software folks is just silly. They're them, we're us. And thinking of version numbers as some sort of (for lack of a better word) "conspiracy" to paint us with the brush of commercialism is just silly.