Ember-CLI 'Ember Update' command

I'm an ember noob going through the ember-cli 101 class. To date, I've been using the upgrade worklow on the ember-cli website, here.

Messing around with the ember-cli help, in terminal, I came across an 'ember update' command that says it updates to the newest ember-cli version.

Is there a difference between the two? Is the 'ember update' command going to be what to use in the future and just isn't fully implemented yet?

Thanks in advance!