Unfortunately, you'll have to buy the Xbox or PS2 version to play it.
Nintendo fans hoping to get their hands on the upcoming Starcraft: Ghost were met with disappointing news today when a Blizzard employee confessed the following on the Battle.NET message board:
" Unfortunately the GameCube version of the game was decided to be dropped. In order to provide the game envisioned by the console team a set and readily available online solution was needed. Unfortunately the GameCube has no online service and since so much work is going in to the online portion, it would be additional work to release only part of the intended game. Nintendo systems certainly aren't something that we are against supporting. Blizzard in its entirety is based upon earlier games for Nintendo systems. The GameCube and Revolution will still be cosidered for future products, unfortunately Ghost will only be made available on the Xbox and PS2 at this time."
When posters inquired further, citing the GameCube's Broadband Adapter, the same employee had the following to say:
" In any case there are many reasons why the GameCube version was cut, but it all boils down to being able to provide the best game experience possible to our fans."
As a consolation, however, he did also say that support for the GameCube has not been cut off, nor has any other Nintendo console (i.e. Revolution) been given the axe as far as future support.