While surfing the web, I fell on this article which I thought I'd link here:
A new breakdown of Android updates has shown that most American models have had far worse support than the iPhone. Looking at at models released 2010 and earlier, Michael DeGusta showed that most were abandoned by their makers quickly. Of the group of 18, 15 don't run Android 2.3, 12 were current for weeks at best READ THE WHOLE ARTICLE