IMO it's not; the difference is one of focus, more specifically is there one or a small number of specific projects or is there a larger slate of things that one can pick and choose from and which may well change their form based on participation *plus* unorganized gatherings (socialization/"hallway track"). My "hacker-con" take on the second form implicitly recognizes that the "hallway track" may well be as continuous as it is at many other conventions....
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