Also, i've only had sarcastic retorts from Yoshida, so I would consider them a bit different, personally.
@yosp and @XboxP3 couldn't be anymore different.
Yoshida, 99% of the time, separates his real business talk from his twitter talk. He keeps teases about E3 strictly on interviews with proper media, and keeps a fine line between trolling and truth whenever answering questions, that make it hard to figure out whether or not he's telling the truth. When he says his twitter role is that of a customer service, he toes that line to the dot, because he rarely betrays that role, aside from when he goes full /s.
Phil Spencer, on the other hand, has loose fingers, and tweets about every darn thing. Game builds, plans, excitement, hype, all the 20 different old IPs that float around his head at any given time, E3E3E3. He feeds his audience by giving them a sneak peak at his world, and at times, pretty much entertains conversations that would be a PR nightmare, like KoToR:Anniversary, etc.