The main reason for the non-investor to attend to marketshare is get an idea of how software availability will be in the future. Not just in sheer number, but in quality. It's not the only thing that matters (monetization does as well), but a huge platform lead
will draw development. You can look at the Wii era and see both heavy resistance from certain developers, and their eventual acquiescence once the share got big enough. Indeed, there are a number of similarities. Wii owners didn't buy nearly as many 3rd party games as other platforms did, but once the lead extended far enough, Activision was finally lured in and COD, predictably, sold millions of copies on Wii.
Games like Civilization Revolution are pretty serious games -- not the normal phone fare. I'd love to see their successors debut on Android and not just eventually meander on by.
In terms of non-gaming software, the deficit has already closed as far as I can tell. There are a few items in earlier stages of development on Android than on iOS, but the last holdouts appear to have already made the leap and seem eager to support the platform fully.
Another welcome:
