It's not the size of your installed base, it's how you use it

This was an interesting graph up on Joystiq, contrasting the growth of installed base between platforms.

While interesting, it's not exactly intellectually honest. For one, the iphone saw a lot of hardware refresh with the same customers upgrading to the 3G/3GS,so some of those are repeat users. Yes, it's still units sold, but for purposes of installed-base discussion, this is relevant.

For another thing, if you are going to talk "consumer tech", then you need to look at other cell phones, DVD players, etc. If you are looking at game platforms, then include the gameboy, the Windows PC. etc. Not sure any of these numbers would beat that curve, but it's worth including (though this example shows that the GBA beat the Wii's growth curve in its first 10 quarters. hmm...). Finally, the attach rate and SW ARPU would also be apple to oranges.

Still, even with all these caveats, it's an interesting chart to consider.