I think it's also referring to the phenomenon as it exists today in every single online multi-player game that features open PVP as well as closed battleground type PVP, not just StarCraft.
The "zerg", as it was commonly known to all players, presented itself to me in the beginning of 2002 in a well-known and still active MMORPG called Dark Age of Camelot (http://en.wikipedia.org/wiki/Dark_age_of_camelot). DAoC-players refer to a mass of ungrouped, uncoordinated players joining in on the large battles between the realms of the game as a "zerg", and to individual players making up the "zerg" as "randoms" (random players; ungrouped) and sometimes as "zergers". The term certainly sprung from the first StarCraft game, but the phenomenon is today embodied not just by NPC units in this or that game, but by actual groups of players, and is seen in practically every MMORPG with PVP.
The "zerg", as it was commonly known to all players, presented itself to me in the beginning of 2002 in a well-known and still active MMORPG called Dark Age of Camelot (http://en.wikipedia.org/wiki/Dark_age_of_camelot). DAoC-players refer to a mass of ungrouped, uncoordinated players joining in on the large battles between the realms of the game as a "zerg", and to individual players making up the "zerg" as "randoms" (random players; ungrouped) and sometimes as "zergers". The term certainly sprung from the first StarCraft game, but the phenomenon is today embodied not just by NPC units in this or that game, but by actual groups of players, and is seen in practically every MMORPG with PVP.