You could come up with any number of reasons to make StarCraft II a nominee for Game of the Year. The single-player campaign was an enthralling romp through an enjoyably cheesy space opera storyline, with some of the most brilliant mission design seen in a strategy game to date. Gone are the days of simply wiping out the enemy's base - with a mission in which lava rises up periodically to wipe out your units, or the Night of the Living Dead homage of zombies attacking at night, RTS developers have their work cut out for them trying to top SC2.
And yet, even the exquisitely-crafted campaign is a pale shadow of the game's stellar multiplayer. Matches in StarCraft II are tense from the very first moment your workers begin harvesting resources to the very last enemy building going up in flames, and that tension never lets up. A match can be won in a tiny skirmish within the first five minutes, or it can be decided twenty minutes later in a huge clash of robots and ship fleets. It's balanced, it's superbly paced, and each of the races still feel distinct and unique. What's more, Blizzard has created a game that matches the original's popularity in competitive gaming - an achievement in itself. That isn't even getting into what can be done with the map creator - how StarCraft fans can create their own minigames to share with the rest of the community.
If StarCraft II delivered in only one of these areas, it would have been a GotY contender - but it has the whole package. It's possible that SC2 will have the most enduring legacy out of any other game released this year. Ten years from now, we'll still be playing StarCraft II, and waiting for Blizzard to announce StarCraft III.