FOR THE RECORD
Sora is the name of Sakurai's freelance organization. It's not really a real development house, it's merely the moniker he uses when auctioning off his services. He basically IS the company, so if must, you could say that Sora is involved in SSBB.
That said, Sora is NOT the name of the team assembled around him for SSBB. The team was people he didn't know (with an office already, that he visited, and remarked on the "horrible" amount of SSBM they'd been playing), that had completed another game recently.
I don't think his partnership with Nintendo here was Sora-based, anyway. That is, it wasn't your standard freelance deal, rather a more personal "coming back for one more game" kind of situation. So Sora as an entity is utterly uninvolved. It's merely plastered after his name on the site because that's how he identifies himself.