A lot of people throw around phrases like "big deal," "game changing," and "transformational when describing VDI. But in VDI is not a big deal. It's not game changing. In fact, VDI is nothing more than a form factor change. It's the same desktop you've always had, just in a different shape. Once you understand this, you'll actually be able to be more successful with VDI.
Many of the alleged benefits people try to push with VDI aren't actually related to VDI. For example, some people say that using VDI means that many users can share a single master disk image, and that that's easier to manage than a bunch of individual images. And it's true: managing one shared image is easier to manage than a bunch of personal images. (And it's probably even "game changing" for them.) But it's not game changing because it's VDI. The game changer is the locking down the desktop. VDI is only how that desktop is delivered to the user.
Now some might argue that the benefits of VDI that are related to VDI itself--consistent performance, accessibility from anywhere and on any device--are in fact game changing. But those are no different than any new desktop form factor.
The desktop PC world began with, well… desktop PCs. They plugged into the wall and you couldn't move them around. That was fine for awhile. Then laptops came out. Laptops had some "game changing" features, like you could take them with you and you didn't have to be plugged into the wall in order to turn them on. Of course laptops had downsides too, like the fact that they were more expensive than desktops while being less powerful.
So we had desktops and laptops. Back then, everyone understood this. They bought desktops for some users and laptops for other users. (Note that they did not run out and buy laptops for everyone--they just bought them where they made sense.)
More importantly, laptops did not change the way that companies managed or delivered Windows. Sure, some companies might have changed the way they delivered Windows at the same time that they transitioned from desktops to laptops (for example, moving from manual installs to automated installs), but changing the Windows deployment method is not because of the laptops--it just happened at the same time.
All of this also applies to VDI. Most people who fail with VDI are those who are making too big of a deal out of it. They're trying to completely re-vamp how they're managing their desktops, including moving users to shared locked-down images and implementing application and user virtualization.
A better way is just to take a step back and catch your breath. VDI is nothing more than a form factor change. Just like laptops provided more [some would say "game changing"] features than desktop computers, VDI desktops provide more features than laptops or desktops. But that doesn't mean that we have to freak out and try to change the world when we go to VDI. (See the related article, "Desktop virtualization is not a 'free pass' for good desktop management.")
So if you want to be successful with VDI, just sprinkle it into your existing environment just like you'd introduce a new laptop model. But don't try to change too much, and certainly don't change the way you're managing Windows just because you have VDI.