Note that I used to believe in the project. I donated money to help them. Then I started to wonder what was going on there. Then for me the clincher was listening to Sam Ruby's presentation at OSCON a few years ago about his experience in trying to get Python running. From then on I've regarded Parrot as a fun project for those involved which I won't take seriously. Since then they've cleaned up development, they are making progress towards a far less ambitious Perl 6 than they set out to create, and I wish them well. But I personally doubt it will ever become widely used as a production platform, and I guarantee that it will never be widely viewed as the prime platform for running a wide variety of dynamic languages. If for no other reason than the fact that they don't have the people and resources to match what is being done on other platforms. (Have you paid attention to what Google has done for JavaScript execution?)
Just consider the facts. Python is a well defined target with multiple ports to different virtual machines. It is basically a perfect example of a realistically complex language in wide use. If you look at his background (see http://en.wikipedia.org/wiki/Sam_Ruby), Sam Ruby is pretty much the ideal person to work on a cross-language virtual machine. There has been literally no person that I've heard of in the Parrot project before or since who has as much relevant experience. And he failed.
The reasons why he failed are complex. But the biggest were all related to specific people problems (luckily mostly fixed since), and a design myopia that believes that Perl 6 subsumes all other dynamic languages, and therefore internal conventions that support Perl 6 efficiently will support everything else well (emphatically not true). Half those problems are gone. The people issues have improved, the design myopia has not.
Wake me up when they get serious about supporting Python. Until then any claims of "all dynamic languages" should come with huge disclaimers.