And it's not a derivative work of the Linux kernel? I don't know much about how Android is structured, but I thought people were complaining that Google didn't push their changes upstream into the main Linux kernel, which would imply that it's part of the Linux kernel.
Presumably Google has published the Honeycomb kernel (I didn't bother to verify this), but that's not interesting. The other 90% of Android is non-GPL userspace code.