As an aside, even pure-Perl Cor will be faster that Moo/se, but I can't say much more about that right now.
*Everything* is faster than Moose so…
For my part, the syntax and its power look nice. All seems quite well thought out; what I skimmed on the wiki sounds terrific. I would maybe still argue it’s better on the CPAN—even if there is core support necessary to go with it—before the core to gauge adoption and suitability. If it’s good—appropriate, doesn’t drag a bunch of stuff down because of core changes—it will see quick adoption and clean-up and such making it even better for the core. If not, it will avoid a lot of fights, core issues that could be rolled back, and problems going forward. I’d like to hear what people like dave_the_m think about it.
Sidenote: This is the first I’ve heard about it and I find that a little troubling though I understand that opening everythig up to committee is a good way to prevent progress.