Should be C, right?
The router rewrite happened in the release candidate versions, before the final release in September. Also, the upgrade to version 4 from 2 is smoothly, with no breaking changes.
Angular 2+ uses virtual DOM. It can use native virtual DOM or simulated virtual DOM for browsers that still doesn’t support it.
Again, it’s not clear about which version of Angular your talking about, since Angular 2+ has one-way data binding as its default.
I’m confused. Are you talking about about Angular 2+ or AngularJS? Before It was Angular 2+, but your view is about AngularJS.
Acho que o time do angular também notou isso e acabaram por substituir o SystemJS pelo Webpack no beta da AngularCLI. Já deu uma olhada lá como está agora? ;D Acho que a mudança foi positiva.