I was hoping before he was unveiled that Luigi would get reworked so his entire move set revolved around the Poltergust 5000, even if many of the moves did the same basic thing (e.g. the air chop would be a quick vacuum hose swipe). Alas, it appears it is not to be. Still, I'm glad the vacuum made it into the game. Luigi's Final Smash in Brawl was weird and useless.
I suppose, since Sakurai doesn't explicitly say the Poltergust 5000 is Luigi's Final Smash, that Luigi could have it as part of his regular moveset (maybe in a similar fashion as Zelda's Sheik transformation) and this pic is taken just after the Final Smash is activated where the stage dims and the character glows. I won't hold my breath.