Thanks for that. I went over to the CCC forum. Mike B says there (in general terms -- not with respect to just Lion) that to clone a PPC and an Intel Mac to an external drive, two such drives are needed, one formatted as APM and one as GUID. I know that is wrong up to and including Snow Leopard -- at least it is wrong for DU as the cloning tool.

I posted a question there. So I'll look to see Mike B's answer.

I'm not clear about using Time Machine and one external for both my PPC and Intel Mac. I'd have to have, of course, two partitions on the external. But how should the external be formatted -- APM or GUID?