Gotta agree with Oasis up there on one thing, the internet wouldn't explode if Ridley is a character. I mean, yeah the Smash fandom would go nuts, but people outside of it wouldn't notice at all. Ridley's smash "legacy" is very much an intern thing for Smash fans only. The only character who's inclusion has been so enormous that it's been reported on big news sites that aren't about gaming, like Yahoo, is Sonic when he was announced for Brawl. I think it was reported somewhere that the Brawl Dojo had 1 million visits on the day Sonic was confirmed, and was momentarily down when he was first announced, though I can't provide a source for that. That my friends is making the internet explode, and let's get real here, while Ridley is requested a ton he's still nowhere near the demand Sonic got, that was out of this world, no character has been so requested before or after his reveal, and no character has the potential to be requested so much either.
No doubt Ridley would still be one of the biggest newcomers they could announce for this game, but his reveal wouldn't take down any sites beyond Smashboards, and Smashboards goes down with every newcomer reveal anyways. The biggest reveal for this game has already happened though, and that was with Mega Man, and even still Ridley is outclassed by Mewtwo and probably K. Rool too.