Much better than GC version
Nothing much has been changed, but the new control rules.
It's dead accurate and very responsive. Now it's much easier to gather your pikmins and aim to attack enemies.
Also graphically, 480p and widescreen is now supported -
If you already have a gamecube controller and a gamecube memory card you may consider buying an old gamecube version, for it's cheaper. But if you want an overall better experience, go for the Wii version.