As soon as Windows 8 Pro (Microsoft) was released, I upgraded my personal computer. The upgrade experience took a bit longer than I expected (about 3 hours). However, the upgrade performed as advertised. A screen shot of my new desktop appears below.
I have been using Windows 8 Pro now for over a week, and I can report that the upgrade was well worth the minor upgrade cost ($39.95 via direct download). You will find many excellent reviews of Windows 8 Pro available on the Internet, so I will not repeat those efforts. I will only add that my upgrade experience went well and I am delighted with this newest release of Windows.
PS: I run Windows Phone 7.5 on my mobile device, which interfaces perfectly with Windows 8 Pro...