Except for the fact that a lot of the higher ups at MS have always been skeptical of the XBox Division, and the threat of shutting it down has been in play since day one. You never hear about anyone at Sony actively looking to shut down their entertainment division, despite the stumble with the PS3 early on, the Playstation name has remained one of the stakes holding up the console gaming tent.
By the same token, Microsoft literally stumbled into early generation dominance this time around just by being out of the gate a year earlier. I had an OG XBox and watched MS completely dump the hardware as soon as the 360 hit the market, and I see them all but doing the exact same thing now with the 360, while Sony continues to announce pretty big titles for the PS3 even with the PS4 on the horizon.
From the standpoint of which company I believe is in it for the long haul, I can look behind Sony and see a company that continued to support their products to at least a serviceable degree for years after it would have been acceptable and in some cases even preferable for them not to, while Microsoft's past is littered with hardware they put out and abandoned within months due to initial poor sales figures.
So when you say Sony has more of a chance of pulling out instead of standing firm and working to correct mistakes, I'm not completely sure where that's coming from. No company is perfect, but when I look at Nintendo and Sony, I see companies much more eager to satisfy their customer base and fix the ills of their product lines than Microsoft will ever be.