A lot of people think that desktop virtualization and VDI are about saving money. But I don't think that's true. Desktop virtualization has a lot of advantages, but typically it ends up costing more money than traditional desktops. (But that's ok. It's fine to spend more money for more features.) But if you're trying to do desktop virtualization just to save money, you were probably fed a line of horse shit by someone. (Which is fine, as long as you knew it was happening.)
First, I should point out that I think most cost analyses are total junk whose results can be "gamed" to prove whatever point you'd like to prove. That said, a lot of people still try to do desktop virtualization to save money, (be it capex or opex), but desktop virtualization is not about saving money.
This is not to say that desktop virtualization is not worth doing. In fact there are a lot of advantages to desktop virtualization: Security. Availability. Faster installs, adds, moves, and changes. Easier disaster recovery. Flexibility. Reliability. But all these advantages (which are awesome!) cost money. And implementing desktop virtualization to get these advantages costs more money than not implementing desktop virtualization.
And you know what? That's ok.
It's totally ok to pay more for desktop virtualization since desktop virtualization gives you awesome new features. This is the way the world works. More features = more money. I often explain this in terms of cars. If you decide to replace an old shitty car with a new one with heated seats, bluetooth navigation, and computer-controlled automatic parallel parking, that new car will be more expensive than your old car. But that's ok because that new car has those awesome new features. So it's ok to spend more on the new car than the old car.
The same is true for desktop virtualization. Desktop virtualization gives you some of the awesome new features that I listed above. But in order to get those awesome new features, you have to pay for them. That's just the way the world works.
Now at this point you might be thinking that this is total hogwash--that "more money for more features" doesn't apply to computers what with Moore's Law and all. But that's hogwash too. Take Blackberries, for example. Giving your users Blackberries is more expensive than users without Blackberries. You have to buy the devices, the data plans, the Blackberry Enterprise Server, the licensing, the training, the support contracts… all of that is additional costs you have for Blackberries that doesn't exist if you don't use Blackberries. But does that mean that no one will use Blackberries since they cost more? Of course not! IT folks recognize that while having Blackberries costs more than not having them, they provide many new features that are awesome and worth the money. So we pay more for Blackberries.
So why isn't the same true for desktop virtualization? What crazy world do we live in where desktop virtualization has to be cheaper than traditional desktops? Why the hell do we want new features and higher availability and access from anywhere but then we STILL expect all that new capability to be cheaper?!?! What kind of crazy bizzaro world is that??
An attempt to save money with VDI
I was explaining this at one of our Desktop Virtualization 2011 events a few weeks ago, and someone challenged me on this. He said that for them, desktop virtualization was cheaper. He explained that right now they're spending $1,000 per desktop for new equipment every four years. If they go to VDI, they can buy $200 thin clients instead of $1,000 desktops. Then they can use some of the $800 saved per desktop to buy the back-end servers, storage, licenses, etc. for the complete environment. All in, they're saving $200 per desktop by going to VDI.
At first you might think, "ok, so for this guy, VDI is about saving money." But there are actually are several problems with this example and this "savings" is total BS.
First, you can buy PCs for $300 or $400. So I would argue that the best way for this guy to save money is to stop buying $1,000 PCs and to instead buy $400 PCs. Now you might argue that he actually needs $1,000 desktops--that his users are "power users" and that they actually need that much computer. Ok fine. But if that's the case, then there's no way in hell that $200 thin client powered by $500 of back-end VDI kit is going to come anywhere close to delivering the computing power and user experience they need.
So in this guy's case, he's saving money not by going to VDI, but rather by drastically cutting down the amount of desktop computing that he's delivering to his users. And he can do that with the $300 PC route--he doesn't need VDI to do that.
The REAL reason people "save" money with desktop virtualization
Ironically the only way people save money with desktop virtualization is because they use the desktop virtualization to deliver an inferior desktop product when compared to their existing physical desktops.
So sometimes people will say, "I'm going to VDI. That will be cheaper because we're going to have shared (and therefore locked-down) disk images which means the users can't screw things up, and that will be cheaper to manage than the current 'Wild West' world of personal images." Again, that's true. But the money savings is coming from the fact that you're locking down your desktop images, not the fact that you're using VDI. And again, if you just wanted to save money, I'd suggest that you lock down your desktops but that you skip desktop virtualization.
To be clear: there are a lot of wonderful and perfectly valid reasons to virtualize your desktops. It's just that saving money is not one of them. And if you use desktop virtualization as your excuse to completely overhaul the way that you deliver desktops, well it's the complete overhaul that's saving you money, not the actual desktop virtualization.
But at the end of the day, you gotta do what you gotta do. And if you really believe desktop virtualization is about saving money, then more power to you. I'll even help you prove it even though I think it's total crap.