So far that is true. At this time there is at least 4-5 different versions of Android running successfully on the Nook Color:
Version | Code Name | EMMC/SD | Comments |
---|---|---|---|
2.1 | Ecclair | emmc | Default OS as delivered by B&N |
2.2 | Froyo | both | Probably the most stable overall at the moment. |
2.3 | Gingerbread (CyanogenMod version) | emmc | Also quite stable |
3.0 | Honeycomb | SD | Hugely popular. |