Never used ember but that deserves a pretty complete write up about what was done and how.
Nice work.
Nice work.
A handlebars template might look like this:
<div class="foo">
{{#if enabled}}
<p>I'm enabled!</p>
{{#end}}
</div>
This uses the knowledge of Handlebars to make the diffing algorithm smarter: you don't need to check if the <div> or its class has changed, it never will. You don't need to check if the <p>'s contents have changed, it never will. This means less to diff, which means more speed.
This is the advantage of using a declarative syntax for templating: this analysis can be done entirely at compile time.