Gingerbread seems to be the Windows XP of the Android ecosystem right now, with some 65% of the entire userbase despite the software being released at the tail-end of 2010. Honeycomb, despite all the work that Google engineers threw into it, never caught on except among the most hard-core proponents of Android-powered tablets. Like Windows Vista, Honeycomb is an operating system that looks good from a distance, and reveals warts upon closer inspection. Does this mean that Ice Cream Sandwich, easily the easiest and most beautiful release of Android, is Google's Windows 7?
According to the Android Developer Platform Versions page the most recent version of Android has captured just a sliver of the market, a meager 7.1%, since it was released nearly eight months ago. Phone vendors around the world have had to scramble in order to prepare devices for this latest update, which has much more sophisticated hardware requirements than any version before it, and they're struggling with problems such as bolting on their own UI elements on top of the new operating system and converting existing customers ... many of whom are still locked into two year contracts with older devices.

To say that Google could have handled this roll out a bit better would be an understatement, but it does lead to an interesting question:
Does Google See a Smart Phone as an Appliance?
In a number of cases, we're seeing phones released and then seemingly forgotten about by the vendors. A phone released in the summer may not receive a new version of Android released in the fall. Sure, there will be incremental updates, but no round numbers. If customers want to go from 2.x to 4, they need to buy a new device. The same thing was seen with most devices that shipped with 1.6, as fewer than a dozen models were capable of being updated to 2.1 afterwards.
This is very different from how Apple handles many of their mobile devices, as those units are usually able to receive updates for just over two years before being locked out of further upgrades. That said, Android's upgrade path seems to be very similar to how phone vendors have typically managed their software updates. People who want to get the latest and greatest software need to also buy the latest and greatest phone. The software is inseparable from the hardware. The same thing can be said about the software controlling our refrigerators, washing machines, and toaster ovens. I've yet to see any of my Toshiba appliances bug me to update their software.
If this is the way Google sees the devices running their mobile operating system, then I can completely understand why there is usually such a slow adoption rate for updates, and why many phones less than a year old will never see them. A phone is a phone is a phone, and the fact that it can install software and act like a computer is just an added bonus for the people who buy into the platform.
Going this route, Google and the vendors that produce hardware around the Android software are free to focus more on market segmentation rather than ensuring forward compatibility. When we go to the electronics shop to buy a refrigerator we are greeted with dozens of units in every color and size, and they're all the same shape. When I buy a refrigerator I know exactly what it can and can't do, and I have no expectation that it will be upgraded for free down the road. Any upgrades, be they ice cream makers or air-flowing buckets, would have to come out of my own pocket and there would be a very short window for these decisions. The same can be said about almost any Android phone more than a year old.
Software Isn't Free
Microsoft seemed to get a number of people hooked on the idea of free, substantial upgrades with Windows XP. Service Pack 1 was a night-and-day improvement over the initial release of the operating system in 2001. Service Pack 2 set the bar even higher, turning Windows XP into an operating system that you could trust so long as your computer didn't have any cheap components. The third and final Service Pack made the system even more stable and secure than anything before it, and arguably more secure than Windows Vista. Each Service Pack introduced new functionality, tweaked UI elements, and changes that people loved or hated with a passion. Millions of people around the world still trust Windows XP on their system despite the software being abandoned by Redmond several years ago.
Apple changed all of this with iOS, though. People running the mobile operating system were able to upgrade their devices for free1 and receive a lot of extra functionality with very little work and zero money. On top of this, Apple's App Store has trained people to believe that decent software can be produced for free and that's typically good enough. Why pay money for something when we don't have to?
Google (and Microsoft) know this sort of economy is not realistic. Good software engineers cost money. A lot of money. Giving applications away or expecting tiny banner ads placed in software to pay the bills is beyond crazy. They need to make sure that people keep buying real, physical products that improve over time. These improved products will have access to a greater range of better software. That better software will, hopefully, cost real money. People who are willing to spend a lot of money every month to pay for a data plan will have less trouble forking over money for excellent applications when the devices will support new functions and features. People who don't want to spend a great deal of money can still get their hands on a mobile appliance, but it's little more than a gateway drug ... a taste of what they might experience with a better phone in the future.
People will naturally continue to use their phones as best they can. Download software and become more familiar and competent with the Android system. When the phone contract is up and people have grown tired of their phones, they'll make the trip to their local phone store to find a more advanced phone also running Android. Just by typing in a Google username and password every app, every scrap of data from our old phone will be magically transported to the new appliance. Who wouldn't want this? From here, people will be able to get better software and may even pay a good amount of cash to get them. They'll tell their friends, and word of mouth will help propagate the platform even more.
This is the plan, anyways ... I think.
It makes sense, too. If people are always upgrading their software, the old hardware is good enough. While that's great for the consumer, it's not great for the vendors or Google as a whole. The idea is to have a constant churn of Android devices, much like we see with other appliances that people outgrow. We don't usually throw away our older TVs when the time comes to replace it with something newer; we move it to the bedroom or give it to the kids. The same is being done with cell phones. Once somebody is done using one device it gets handed down to another person, and the cycle repeats itself.
This is why, I believe, most Android devices will rarely see a full-point upgrade.