Yes IBM seem to be interested and it looks like apple themselves may pick up PPC development.
The problem I have is that the chase for MHz is an extremely expensive affair. IBM have long made chips for their high cost AIX servers and similar. That business is profitable for them. Their x86 PC business is actually one of the least profitable. They released the PPC POP spec of course and produced a chipset for it .. but it never got the attention it deserved.. and is past its market use by date now.
I really have problems believing that this market is viable in the long term. I tend to think either Motorola or IBM will lay their costings out on the table for Apple.. and then put it too them straight..