"Debian Within a Darwin System"

[Michael]

On the Debian GNU/Linux PowerPC PowerMac Page 
(http://www.debian.org/ports/powerpc/inst/pmac) the second paragraph closes by 
mentioning that "Shortly, you may also have the option of running Debian within 
a Darwin system."  What exactly does that statement mean, and when is shortly?  
Thank you for your help.  
Michael