2) : is just a shorthand for v-bind (ie; v-bind:disabled="is_disabled()" is aliased by :disabled="is_disabled()"). and this basically allows you to run pure javascript code inside of it.
3) the only other syntax to know is, v-for and v-if, but thats pretty self explanatory i believe.
<h3 v-if="user.name">{{name}}</h3>
<h3 v-if="!user.name">What is your name?</h3>
<h3 v-if="user.role == 'admin" && user.name == 'james'>hello super user {{name}}</h3>
i like this approach more than JSX where you have several if else clauses mixed into your HTML. it's kind of like pattern matching if you like that sort of thing.
or you can simply do <h3>{{some_message()}}</h3> and just handle the logic inside the some_message() method.
1) v-if is not html. In html if you see <h3 ...> you immediately think, "there's a level-3 header element here". The thought "there's a level-3 header element here if..." is something new you have to learn for Vue.
2) Shorter is not always easier. For example, using quotes to delimit logical expressions makes it easy to make errors. See the misplaced quote here?
<h3 v-if="user.role == 'admin" && user.name == 'james'>hello super user {{name}}</h3>