The CyanogenMod team is taking a page out of Google’s book and announcing that it’s kind of dropping support for the Google Nexus One (and other devices with first-generation Qualcomm Snapdragon processors).
While CyanogenMod 7.x will continue to be available on these devices, CyanogenMod 9 and later will not… at least not officially.
CyanogenMod makes aftermarket firmware based on Google Android. Basically, if you don’t like the software that came with your Android phone or tablet, you can try to replace it with CyanogenMod, a custom version which offers performance tweaks, customization options, and more.
CM9 is based on Android 4.0 and CM10 is based on Android 4.1, while CyanogenMod 7 uses Android 2.3.
The CyanogenMod team says that devices with earlier Qualcomm Snapdragon processors don’t have the media libraries to work with APIs in Android 4.0 and later. This is particularly a problem for encoding and decoding devices.
The Google Nexus One has another problem, which is that you need to repartition the internal storage space to make room for Android 4.0 and other operating systems that require more space than Android 2.3.
Some folks have been unofficially porting CyanogenMod 9 to the Nexus One and similar devices for a while. But flashing those builds is a little trickier than installing most custom ROMs, and some features may not work.