Blizzard sure knows how to rake in the money - just look at how much they’re making from World of Warcraft. Possibly feeling they need to continue making incredible profits, Starcraft 2 (the single player campaign, anyway) will be released as a trilogy (first Terran, second Zerg, third Protoss) being three seperate products. I think the excuse that the experience is too big to release as one game isn’t really acceptable in this day and age, forcing consumers to purchase their game three times over. It could ship as a three dual layer DVD package (and I do doubt each “game” will be be dual layer, probably single) with a BD-ROM package available using only one disc (similar to Half Life 2, being either 5 CD’s or 1 DVD). It’s not a matter of storage. This game would want to ship at a good price point (which isn’t very likely), meaning to get the full experience you’d probably be up for over $150.

What do I think will end up happening? If the product allows full multiplayer from each “game” (featuring all sides) then people will purchase one “game”, then pirate the other two. Really, it’s been ten years since the first Starcraft game was released, couldn’t Blizzard have taken the time to make the game a single complete package like, oh I don’t know - Starcraft. I miss the days of Rock n’ Roll Racing.
You can read more via Kotaku.