I know all about Powershell and use it routinely. I still fail to see what in the hell it has to due with Windows being entrenched in business. As an admin it helps me greatly (and well, required since MS exposes less and less critical server management features in GUI's these days), but it means dick-all to the end user. Was Windows flailing about in the enterprise before it existed? If a powerful scripting language/command shell was paramount to being entrenched in business, then why the hell did MS ever get a toehold at all when cmd.exe was absolutely pathetic compared to what was offered in the Unix world?
Windows will continue to survive in the enterprise if it produces platforms that work exceedingly well together and have solid interfaces designed for their form factor at reasonable prices. While it's hardly the dire situation it is with the consumer market, MS's business position is under threat like it hasn't been for the past decade. The prevalence of tablets and phones that run software not produced by Microsoft is primarily the reason for this, when people spend a good portion of their digital lives on non MS platforms it can, and in same cases already has, start a cascade effect. The mantra of "Good Enough" helped MS greatly in the preceding years, it may end up hurting them now. There are still many arguments to make for going with Microsoft in your business, but if I was in a meeting and management wanted to go to Google Docs for a good potion of the company, I would rightfully be laughed out of the room if I responded with "But..but...POWERSHELL!".
I mean for pete's sake, I've heard some ardant MS apologists since Win8 came out like never before (really, Microsoft fans can no longer smirk at Apple zealots IMO), but stating MS is A-OK in business going forward becauuse of powershell is a new angle of delusion.