As shown by this chart on Motorola's support page, the list of phones getting left behind with older versions of Android grows by two with the Charm and Flipout.

Motorola has decided to pull back on plans to update its Charm (T-Mobile) and Flipout (AT&T) handsets with Android 2.2 Froyo.

Of course, that means that the smartphones, which were released with Android 2.1 back in the fall, will remain on Eclair indefinitely. The handsets join a growing list of Motorola phones being left behind on older versions of Android. Most recently, the company decided that the Cliq XT would stay on Android 1.5 and never see features such as Google Maps Navigation or live wallpapers.

Looking at the list of devices represented on Motorola's support page (see above chart), it's apparent that the company doesn't intend to spend much time or development on older devices. Let's hope that new handsets such as the Atrix 4G or Droid X get more than one update.

As to why these handsets aren't going to see much beyond Android 2.1 could be anyone's guess. Motorola talks of wanting to provide an "optimal customer experience," but that may be interpreted many ways. Perhaps the problems stem from having to work with so many form factors and hardware configurations.

On the other hand, the issues could stem from the Motoblur interface, which overlays Android. Perhaps Moto integrated the custom UI too heavily, which prevents it from acting quickly to roll out updates. Another likely scenario might be that these phones aren't selling as well as anticipated and that it would be a waste of time and resources to work on updates for such a limited quantity of devices.