Philip Greenspun, Internet entrepreneur and MIT professor, has recently reviewed Windows 8 and came down to a conclusion that may really upset Microsoft: Windows 8 is a Christmas gift for someone you hate.

Greenspun claims that Windows 8 lacks the most important features currently available on Android, iPads and previous Windows versions, such as “a permanently on-screen Back button,” a “permanent hardware Home button,” and a Start Menu, respectively.

“Microsoft has had since October 2008 to study Android. It has had since June 2007 to study iPhone. It seems as though they did not figure out what is good about the standard tablet operating systems,” he wrote on his blog.

What more, Greenspun recommends users to keep a Windows 7 computer close, just in case they need to search for step-by-step instructions on how to access some Windows 8 features. That’s because when “you go to a web browser in the desktop interface you can see the tablet interface that you’re getting advice on how to use.”

“The only device that I can remember being as confused by is the BlackBerry PlayBook. I would find this machine a lot more useful if it simply ran Android as a sub-environment and did so in the right-hand third of the screen,” Greenspun continued.

While noting that tech journalists were wrong when they offered Windows 8 positive reviews, Greenspun explained that Windows 8 is nothing more than a new, different and complicated product.

Of course, he criticizes the Modern UI and the fact that you have to restart the computer or launch an app from the “tablet interface.” Fortunately, this isn’t true, as you can also pin apps to the Taskbar and restart the computer by pressing Alt + F4 from the desktop.

“Suppose that you are an expert user of Windows NT/XP/Vista/7, an expert user of an iPad, and an expert user of an Android phone…. you will have no idea how to use Windows 8,” he concluded.