It took a while, but the most recent version of Android is now the most popular version, as upgrades have finally been doled out to a large fraction of the platform's user base. Of course, the news comes potentially just a few weeks before the Android 2.3 update rolls around and we start this all over again, but for now Google has done a good job of getting as many people up-to-date as possible.
It's not a huge fraction of the Android population. In fact, the number of people with Android 2.2 isn't even a statistical majority. However, it is enough to make it the most-used version of the OS, just barely edging it over Android 2.1. Here's the full breakdown:
- Android 2.2: 43.4%
- Android 2.1: 39.6%
- Android 1.6: 10.6%
- Android 1.5: 6.3%
- Below Android 1.5: < 0.1%
The problem for many of the people with a lower version of the OS is they simply haven't received the update yet. It has nothing to do with them rejecting or being unable to find the update. It's just not available.
Some of the older, legacy phones will never be able to update and as such will remain a statistic here until the users upgrade the phone itself. That could take years.
Google is planning to totally revamp Android when it hits 3.0, making the requirements stricter and more uniform. Until then, though, it's a gamble as to whether or not the phone you buy will be updated in a timely manner. Hint: Buying a phone with the word "Nexus" or "Droid" in its name is usually a good idea.