Still no template inheritance! I feel like I'm taking crazy pills when that's the one feature I need / care about and none of the newer template languages implement it. I'm spoiled from Django/Jinja2/twig.
I'd consider this functionality in the future, but Emblem's bound by the constraints of Handlebars.js. In the meantime, most JS frameworks that you'd use Handlebars/Emblem with provide something pretty close to template inheritance. You'd achieve something similar in Ember with 'outlets', if I understand correctly.
Jade has template inheritance, mixins, includes and plenty of other cool stuff. If you haven't, you might want to check it out: https://github.com/visionmedia/jade
