Why did Microsoft do it?

Lets say MS goes away (which I don't think so) You have overpriced mac which has less than 10 percent of market share or you have linux which is unintuitive and often not supported by hardware manufacturers with drivers and overall support. Someone else will have to come along to take their place and as long as there is enough money in it, MS will continue. Realize that PC are just a part of the business, Business computers and servers are another part of it. They still have Xbox which is still popular. Just don't see them going anywhere.

What I do see that Jobs is gone, all those visionary products are gone with him. Remember when Apple got rid of Jobs the first time, it was not until he was brought back did they start doing well again. If they slip, it will make it that much easier for MS to maintain even without a blockbuster.