Nadella may deserve some, perhaps a lot, of the credit, but, most of the software and technology developments were well underway and even ready for deployment, before Ballmer had even declared that he was leaving.
There may be a new attitude within the workplace, and perhaps in the minds of may Wall Street types, but, development of new software and hardware, and even services, takes a lot longer than 3 months.
Nice hype, though. I’m not taking anything away from Nadella, but, let’s give credit where credit is due.
I was speaking with a MS guy today who is involved closely with Office 365 product management and their previous BPOS product, and he said that Office for the iPad had been done for a year and they sat on it, because Ballmer would never have released it.