Well Microsoft makes more money from all the other parts of thier company, Sony is only making profits from it's gaming divison, and Nintendo doesn't do anything else but games. So while the other companies have apps and stuff, it is pretty easy to see why some are jumping to conclusions, Microsoft doesn't need gaming, where as Sony and Nintendo can't survive without it. It just naturally makes Microsoft the one to be content with being an entertainment box that plays games, while Sony and Nintendo make game consoles that can be used for other things.
I think Microsoft will continue to be involved with gaming, because the Xbox is their best consumer name product, it gives them street cred, they can use gaming to accomplish other things so their's no reason to bail. I just think in the future Microsft won't make many core new IP's, they will be a good console with good games, but there will only be 2-3 mainline Micrsoft franchises, the rest of their exclusives will be Kinect games, they of course will continue to aim at being the big third-pary console. That's still a gaming console, but they aren't going to try as much niche gaming stuff as the others.