There were some big changes between the two.
This
<ion-list option-buttons="[{text:'hello',type:'button-positive',onTap:tap()}]"
on-delete="onDelete(el)"
delete-icon="ion-minus-circled"
can-delete="true"
show-delete="shouldShowDelete"
on-reorder="onReorder(el, startIndex, toIndex)"
reorder-icon="ion-navicon"
can-reorder="true"
show-reorder="shouldShowReorder">
<ion-item ng-repeat="item in items">
{{item}}
</ion-item>
</ion-list>
Becomes this
<ion-list show-delete="shouldShowDelete"
show-reorder="shouldShowReorder">
<ion-item ng-repeat="item in items">
{{item}}
<ion-delete-button class="ion-minus-circled"
ng-click="onDelete(item)">
</ion-delete-button>
<ion-reorder-button class="ion-navicon"
ng-click="onReorder(item, $fromIndex, $toIndex)">
</ion-reorder-button>
<ion-option-button class="button-positive" ng-click="tap()">
Hello
</ion-option-button>
</ion-item>
</ion-list>
Take a look at this release note