I run business software (quickbooks, excel, word, cad viewers, etc.) and need multiple programs on my screen at once. Not to mention, I also game while I work (I'm the boss), so many times I'll have a window of CivV or some other game running as well.
You can run multiple programs with W8, no need for third part software...it is just like windows 7...
You can have games like Civ V run in one window and have other problems run in another...you can quickly get side-by-side windows just like you can in Windows 7...you will have no problem having multiple Excel, Word, etc files open and on screen at the same time...
The only things that cannot be displayed onscreen simultaneously are the W8 "apps" which you probably would not be using anyway...these are the special apps designed for people on phones or tablets, and include things like a special "mail" app or "weather" app (the same things you would see on an iphone or ipad)....
W8 is not a failure of software, it is a failure of advertisement...for example, people read statements like "you can't have 2 apps open at once" and immediately think W8 does not allow you to run 2 programs on the same screen (one could not be farther from the truth)...Microsoft has not failed in creating a solid product, but rather has failed at being louder than the W8 critics who have made false or ambiguous claims....claims that, unfortunately, have facilitated misinformation....