Windows is not going away any time soon. Windows Phone 8 is not that big of deal right now but it is growing. The thing about Windows Phone 8 is that it works very well with other Microsoft software like Microsoft Exchange and Microsoft Office. Many AutoCAD users use many Microsoft Products (like Office and Exchange.) Windows Phone 8 will get adopted, how much, I have no idea. In the U.S. it only has a small market share (at the moment) but it is growing. Windows 8 will eventually replace most of Windows XP, Windows Vista and eventually Windows 7. Honestly that may not happen until Windows 9 comes out, but you get the idea. Windows, for the moment, is here to stay in the enterprise and in small business.
Autodesk has already begun rolling out other apps onto Windows 8 and Windows 8 RT. They have Sketchbook available now. Putting their software on Windows 8 is easy enough. Just take the software and make sure it works in this version of the OS. Windows Phone 8 and Windows RT is a bit different. But as a CAD Manager and IT guy, I would much rather give my users a Windows 8 based tablet than an iPad. Why? Because it’s Windows, that’s why. I can get one software version and put it on their desktop, laptop, or Windows Tablet (with the proper amount of licenses of course.) But if I give them an iPad or Android tablet I have to get and manage yet another set of programs and operating systems. I don’t want to do that.
I am nearly certain that Autodesk understands this and I am willing to bet that all 2014 versions (assuming there will be AutoCAD 2014 and the like) will be Windows 8 compatible. I also think that we will see AutoCAD WS on Windows Phone 8 as well.