Perl 6 is parrot's main reason for being, but IMHO it's /very/ important that it be a viable platform for running other things on, and that it actualy be used for that. It'll make it that much more likely that XS-like things that currently rely on reverse-engeneering and people's free time will, in the Parrot World, get supported by vendors. If parrot becomes the platform of choice for Python, Ruby, and Perl6, and vendors can support all three in One Fell Swoop, it's that much more likely that they will.
And, wonderful as CPAN is, think how much better it will be if you can take existing Python and Ruby code and integrate it into your Perl6 project without even thinking about it, with a simple use Whatever :py; (or whatever it ends up being).
Parrot being the defacto standard for other languages makes somthing that would be wonderful (and somwhat unlikely) that much more likely -- a parrot interpreter having hooks into a decent percentage of the installed base of browsers, and I very much look forward to being able to script browsers in parrot.
Perl6 may be the reason for building parrot, but if it becomes the only reason for running parrot, I'll be very disapointed.
(And I very much hope that ActiveState sees the light about taking an active posture in supporting parrot for it's other languages.)
Update: I was going to post this as a sepperate node, but I don't really have that much to say on it -- FoxtrotUniform++; couldn't have said it better myself. But I'd just like to note somthing -- "how do I tye my scheme and ruby code together" is a parrot issue, even though it has nothing to do with perl and a lot to do with scheme and ruby. It should probably be considered on-topic ground... but as with every other interface between ontopic and offtopic, it in no small part around here will depend on the actions of the voters, monks+ and editors who happen to be around when it comes up. One of the great things about the monastery is how self-regulating it is, normaly with a minimum of bickering.
Confession: It does an Immortal Body good.